diff -r 3f1644328d06 -r a33d1c19cbc8 jdk/src/java.base/share/classes/java/util/Arrays.java --- a/jdk/src/java.base/share/classes/java/util/Arrays.java Wed Nov 04 12:46:05 2015 +0100 +++ b/jdk/src/java.base/share/classes/java/util/Arrays.java Wed Nov 04 16:44:38 2015 +0100 @@ -25,6 +25,8 @@ package java.util; +import jdk.internal.HotSpotIntrinsicCandidate; + import java.lang.reflect.Array; import java.util.concurrent.ForkJoinPool; import java.util.function.BinaryOperator; @@ -42,7 +44,6 @@ import java.util.stream.LongStream; import java.util.stream.Stream; import java.util.stream.StreamSupport; -import jdk.internal.HotSpotIntrinsicCandidate; /** * This class contains various methods for manipulating arrays (such as @@ -2586,6 +2587,55 @@ } /** + * Returns true if the two specified arrays of longs, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(long[] a, int aFromIndex, int aToIndex, + long[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of ints are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2615,6 +2665,55 @@ } /** + * Returns true if the two specified arrays of ints, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(int[] a, int aFromIndex, int aToIndex, + int[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of shorts are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2644,6 +2743,55 @@ } /** + * Returns true if the two specified arrays of shorts, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(short[] a, int aFromIndex, int aToIndex, + short[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of chars are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2674,6 +2822,55 @@ } /** + * Returns true if the two specified arrays of chars, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(char[] a, int aFromIndex, int aToIndex, + char[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of bytes are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2703,6 +2900,55 @@ } /** + * Returns true if the two specified arrays of bytes, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(byte[] a, int aFromIndex, int aToIndex, + byte[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of booleans are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2732,6 +2978,55 @@ } /** + * Returns true if the two specified arrays of booleans, over the specified + * ranges, are equal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(boolean[] a, int aFromIndex, int aToIndex, + boolean[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) + if (a[aFromIndex++] != b[bFromIndex++]) + return false; + + return true; + } + + /** * Returns {@code true} if the two specified arrays of doubles are * equal to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs @@ -2759,9 +3054,70 @@ if (a2.length != length) return false; - for (int i=0; iequal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + *

Two doubles {@code d1} and {@code d2} are considered equal if: + *

    {@code new Double(d1).equals(new Double(d2))}
+ * (Unlike the {@code ==} operator, this method considers + * {@code NaN} equals to itself, and 0.0d unequal to -0.0d.) + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @see Double#equals(Object) + * @since 9 + */ + public static boolean equals(double[] a, int aFromIndex, int aToIndex, + double[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) { + Double va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Double.doubleToRawLongBits(va) != Double.doubleToRawLongBits(vb)) + if (!Double.isNaN(va) || !Double.isNaN(vb)) + return false; + } return true; } @@ -2794,9 +3150,70 @@ if (a2.length != length) return false; - for (int i=0; iequal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + *

Two floats {@code f1} and {@code f2} are considered equal if: + *

    {@code new Float(f1).equals(new Float(f2))}
+ * (Unlike the {@code ==} operator, this method considers + * {@code NaN} equals to itself, and 0.0f unequal to -0.0f.) + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @see Float#equals(Object) + * @since 9 + */ + public static boolean equals(float[] a, int aFromIndex, int aToIndex, + float[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) { + float va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Float.floatToRawIntBits(va) != Float.floatToRawIntBits(vb)) + if (!Float.isNaN(va) || !Float.isNaN(vb)) + return false; + } return true; } @@ -2827,9 +3244,60 @@ return false; for (int i=0; iequal to one another. + * + *

Two arrays are considered equal if the number of elements covered by + * each range is the same, and all corresponding pairs of elements over the + * specified ranges in the two arrays are equal. In other words, two arrays + * are equal if they contain, over the specified ranges, the same elements + * in the same order. + * + *

Two objects {@code e1} and {@code e2} are considered equal if + * {@code Objects.equals(e1, e2)}. + * + * @param a the first array to be tested for equality + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested fro equality + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return {@code true} if the two arrays, over the specified ranges, are + * equal + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static boolean equals(Object[] a, int aFromIndex, int aToIndex, + Object[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + if (aLength != bLength) + return false; + + for (int i = 0; i < aLength; i++) { + if (!Objects.equals(a[aFromIndex++], b[bFromIndex++])) return false; } @@ -5185,4 +5653,3233 @@ public static DoubleStream stream(double[] array, int startInclusive, int endExclusive) { return StreamSupport.doubleStream(spliterator(array, startInclusive, endExclusive), false); } -} + + + // Comparison methods + + // Compare boolean + + /** + * Compares two {@code boolean} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Boolean#compare(boolean, boolean)}, at an index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(boolean[], boolean[])} for the definition of a + * common and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(boolean[], boolean[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Boolean.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(boolean[] a, boolean[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Boolean.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code boolean} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Boolean#compare(boolean, boolean)}, at a + * relative index within the respective arrays that is the length of the + * prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(boolean[], int, int, boolean[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(boolean[], int, int, boolean[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Boolean.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(boolean[] a, int aFromIndex, int aToIndex, + boolean[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + boolean va = a[aFromIndex++]; + boolean vb = b[bFromIndex++]; + if (va != vb) return Boolean.compare(va, vb); + } + + return aLength - bLength; + } + + // Compare byte + + /** + * Compares two {@code byte} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Byte#compare(byte, byte)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(byte[], byte[])} for the definition of a common and + * proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(byte[], byte[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Byte.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(byte[] a, byte[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Byte.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code byte} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Byte#compare(byte, byte)}, at a relative index + * within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(byte[], int, int, byte[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(byte[], int, int, byte[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Byte.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(byte[] a, int aFromIndex, int aToIndex, + byte[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + byte va = a[aFromIndex++]; + byte vb = b[bFromIndex++]; + if (va != vb) return Byte.compare(va, vb); + } + + return aLength - bLength; + } + + /** + * Compares two {@code byte} arrays lexicographically, numerically treating + * elements as unsigned. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Byte#compareUnsigned(byte, byte)}, at an index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(byte[], byte[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Byte.compareUnsigned(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are + * equal and contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compareUnsigned(byte[] a, byte[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Byte.compareUnsigned(a[i], b[i]); + } + + return a.length - b.length; + } + + + /** + * Compares two {@code byte} arrays lexicographically over the specified + * ranges, numerically treating elements as unsigned. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Byte#compareUnsigned(byte, byte)}, at a + * relative index within the respective arrays that is the length of the + * prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(byte[], int, int, byte[], int, int)} for the + * definition of a common and proper prefix.) + * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Byte.compareUnsigned(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is null + * @since 9 + */ + public static int compareUnsigned(byte[] a, int aFromIndex, int aToIndex, + byte[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + byte va = a[aFromIndex++]; + byte vb = b[bFromIndex++]; + if (va != vb) return Byte.compareUnsigned(va, vb); + } + + return aLength - bLength; + } + + // Compare short + + /** + * Compares two {@code short} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Short#compare(short, short)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(short[], short[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(short[], short[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Short.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(short[] a, short[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Short.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code short} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Short#compare(short, short)}, at a relative + * index within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(short[], int, int, short[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(short[], int, int, short[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Short.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(short[] a, int aFromIndex, int aToIndex, + short[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + short va = a[aFromIndex++]; + short vb = b[bFromIndex++]; + if (va != vb) return Short.compare(va, vb); + } + + return aLength - bLength; + } + + /** + * Compares two {@code short} arrays lexicographically, numerically treating + * elements as unsigned. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Short#compareUnsigned(short, short)}, at an index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(short[], short[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Short.compareUnsigned(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are + * equal and contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compareUnsigned(short[] a, short[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Short.compareUnsigned(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code short} arrays lexicographically over the specified + * ranges, numerically treating elements as unsigned. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Short#compareUnsigned(short, short)}, at a + * relative index within the respective arrays that is the length of the + * prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(short[], int, int, short[], int, int)} for the + * definition of a common and proper prefix.) + * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Short.compareUnsigned(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is null + * @since 9 + */ + public static int compareUnsigned(short[] a, int aFromIndex, int aToIndex, + short[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + short va = a[aFromIndex++]; + short vb = b[bFromIndex++]; + if (va != vb) return Short.compareUnsigned(va, vb); + } + + return aLength - bLength; + } + + // Compare char + + /** + * Compares two {@code char} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Character#compare(char, char)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(char[], char[])} for the definition of a common and + * proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(char[], char[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Character.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(char[] a, char[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Character.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code char} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Character#compare(char, char)}, at a relative + * index within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(char[], int, int, char[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(char[], int, int, char[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Character.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(char[] a, int aFromIndex, int aToIndex, + char[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + char va = a[aFromIndex++]; + char vb = b[bFromIndex++]; + if (va != vb) return Character.compare(va, vb); + } + + return aLength - bLength; + } + + // Compare int + + /** + * Compares two {@code int} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Integer#compare(int, int)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(int[], int[])} for the definition of a common and + * proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(int[], int[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Integer.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(int[] a, int[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Integer.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code int} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Integer#compare(int, int)}, at a relative index + * within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(int[], int, int, int[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(int[], int, int, int[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Integer.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(int[] a, int aFromIndex, int aToIndex, + int[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + int va = a[aFromIndex++]; + int vb = b[bFromIndex++]; + if (va != vb) return Integer.compare(va, vb); + } + + return aLength - bLength; + } + + /** + * Compares two {@code int} arrays lexicographically, numerically treating + * elements as unsigned. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Integer#compareUnsigned(int, int)}, at an index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(int[], int[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Integer.compareUnsigned(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are + * equal and contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compareUnsigned(int[] a, int[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Integer.compareUnsigned(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code int} arrays lexicographically over the specified + * ranges, numerically treating elements as unsigned. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Integer#compareUnsigned(int, int)}, at a + * relative index within the respective arrays that is the length of the + * prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(int[], int, int, int[], int, int)} for the + * definition of a common and proper prefix.) + * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Integer.compareUnsigned(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is null + * @since 9 + */ + public static int compareUnsigned(int[] a, int aFromIndex, int aToIndex, + int[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + int va = a[aFromIndex++]; + int vb = b[bFromIndex++]; + if (va != vb) return Integer.compareUnsigned(va, vb); + } + + return aLength - bLength; + } + + // Compare long + + /** + * Compares two {@code long} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Long#compare(long, long)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(long[], long[])} for the definition of a common and + * proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(long[], long[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Long.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(long[] a, long[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Long.compare(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code long} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Long#compare(long, long)}, at a relative index + * within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(long[], int, int, long[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(long[], int, int, long[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Long.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(long[] a, int aFromIndex, int aToIndex, + long[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + long va = a[aFromIndex++]; + long vb = b[bFromIndex++]; + if (va != vb) return Long.compare(va, vb); + } + + return aLength - bLength; + } + + /** + * Compares two {@code long} arrays lexicographically, numerically treating + * elements as unsigned. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Long#compareUnsigned(long, long)}, at an index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(long[], long[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Long.compareUnsigned(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are + * equal and contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compareUnsigned(long[] a, long[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return Long.compareUnsigned(a[i], b[i]); + } + + return a.length - b.length; + } + + /** + * Compares two {@code long} arrays lexicographically over the specified + * ranges, numerically treating elements as unsigned. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Long#compareUnsigned(long, long)}, at a + * relative index within the respective arrays that is the length of the + * prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(long[], int, int, long[], int, int)} for the + * definition of a common and proper prefix.) + * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Long.compareUnsigned(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is null + * @since 9 + */ + public static int compareUnsigned(long[] a, int aFromIndex, int aToIndex, + long[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + long va = a[aFromIndex++]; + long vb = b[bFromIndex++]; + if (va != vb) return Long.compareUnsigned(va, vb); + } + + return aLength - bLength; + } + + // Compare float + + /** + * Compares two {@code float} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Float#compare(float, float)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(float[], float[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(float[], float[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Float.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(float[] a, float[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + float va = a[i], vb = b[i]; + if (Float.floatToRawIntBits(va) != Float.floatToRawIntBits(vb)) { + int c = Float.compare(va, vb); + if (c != 0) return c; + } + } + + return a.length - b.length; + } + + /** + * Compares two {@code float} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Float#compare(float, float)}, at a relative + * index within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(float[], int, int, float[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(float[], int, int, float[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Float.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(float[] a, int aFromIndex, int aToIndex, + float[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + float va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Float.floatToRawIntBits(va) != Float.floatToRawIntBits(vb)) { + int c = Float.compare(va, vb); + if (c != 0) return c; + } + } + + return aLength - bLength; + } + + // Compare double + + /** + * Compares two {@code double} arrays lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements, as if by + * {@link Double#compare(double, double)}, at an index within the respective + * arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(double[], double[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + *

The comparison is consistent with {@link #equals(double[], double[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return Double.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static int compare(double[] a, double[] b) { + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + double va = a[i], vb = b[i]; + if (Double.doubleToRawLongBits(va) != Double.doubleToRawLongBits(vb)) { + int c = Double.compare(va, vb); + if (c != 0) return c; + } + } + + return a.length - b.length; + } + + /** + * Compares two {@code double} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements, as if by {@link Double#compare(double, double)}, at a relative + * index within the respective arrays that is the length of the prefix. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(double[], int, int, double[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(double[], int, int, double[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if: + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return Double.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int compare(double[] a, int aFromIndex, int aToIndex, + double[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + double va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Double.doubleToRawLongBits(va) != Double.doubleToRawLongBits(vb)) { + int c = Double.compare(va, vb); + if (c != 0) return c; + } + } + + return aLength - bLength; + } + + // Compare objects + + /** + * Compares two {@code Object} arrays, within comparable elements, + * lexicographically. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing two elements of type {@code T} at + * an index {@code i} within the respective arrays that is the prefix + * length, as if by: + *

{@code
+     *     Comparator.nullsFirst(Comparator.naturalOrder()).
+     *         compare(a[i], b[i])
+     * }
+ * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(Object[], Object[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * A {@code null} array element is considered lexicographically than a + * non-{@code null} array element. Two {@code null} array elements are + * considered equal. + * + *

The comparison is consistent with {@link #equals(Object[], Object[]) equals}, + * more specifically the following holds for arrays {@code a} and {@code b}: + *

{@code
+     *     Arrays.equals(a, b) == (Arrays.compare(a, b) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array references + * and elements): + *

{@code
+     *     int i = Arrays.mismatch(a, b);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return a[i].compareTo(b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @param the type of comparable array elements + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @since 9 + */ + public static > int compare(T[] a, T[] b) { + if (a == b) + return 0; + // A null array is less than a non-null array + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + T oa = a[i]; + T ob = b[i]; + if (oa != ob) { + // A null element is less than a non-null element + if (oa == null || ob == null) + return oa == null ? -1 : 1; + int v = oa.compareTo(ob); + if (v != 0) { + return v; + } + } + } + + return a.length - b.length; + } + + /** + * Compares two {@code Object} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing two + * elements of type {@code T} at a relative index {@code i} within the + * respective arrays that is the prefix length, as if by: + *

{@code
+     *     Comparator.nullsFirst(Comparator.naturalOrder()).
+     *         compare(a[aFromIndex + i, b[bFromIndex + i])
+     * }
+ * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(Object[], int, int, Object[], int, int)} for the + * definition of a common and proper prefix.) + * + *

The comparison is consistent with + * {@link #equals(Object[], int, int, Object[], int, int) equals}, more + * specifically the following holds for arrays {@code a} and {@code b} with + * specified ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively: + *

{@code
+     *     Arrays.equals(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) ==
+     *         (Arrays.compare(a, aFromIndex, aToIndex, b, bFromIndex, bToIndex) == 0)
+     * }
+ * + * @apiNote + *

This method behaves as if (for non-{@code null} array elements): + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return a[aFromIndex + i].compareTo(b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @param the type of comparable array elements + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static > int compare( + T[] a, int aFromIndex, int aToIndex, + T[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + T oa = a[aFromIndex++]; + T ob = b[bFromIndex++]; + if (oa != ob) { + if (oa == null || ob == null) + return oa == null ? -1 : 1; + int v = oa.compareTo(ob); + if (v != 0) { + return v; + } + } + } + + return aLength - bLength; + } + + /** + * Compares two {@code Object} arrays lexicographically using a specified + * comparator. + * + *

If the two arrays share a common prefix then the lexicographic + * comparison is the result of comparing with the specified comparator two + * elements at an index within the respective arrays that is the prefix + * length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two array lengths. + * (See {@link #mismatch(Object[], Object[])} for the definition of a common + * and proper prefix.) + * + *

A {@code null} array reference is considered lexicographically less + * than a non-{@code null} array reference. Two {@code null} array + * references are considered equal. + * + * @apiNote + *

This method behaves as if (for non-{@code null} array references): + *

{@code
+     *     int i = Arrays.mismatch(a, b, cmp);
+     *     if (i >= 0 && i < Math.min(a.length, b.length))
+     *         return cmp.compare(a[i], b[i]);
+     *     return a.length - b.length;
+     * }
+ * + * @param a the first array to compare + * @param b the second array to compare + * @param cmp the comparator to compare array elements + * @param the type of array elements + * @return the value {@code 0} if the first and second array are equal and + * contain the same elements in the same order; + * a value less than {@code 0} if the first array is + * lexicographically less than the second array; and + * a value greater than {@code 0} if the first array is + * lexicographically greater than the second array + * @throws NullPointerException if the comparator is {@code null} + * @since 9 + */ + public static int compare(T[] a, T[] b, + Comparator cmp) { + Objects.requireNonNull(cmp); + if (a == b) + return 0; + if (a == null || b == null) + return a == null ? -1 : 1; + + int length = Math.min(a.length, b.length); + for (int i = 0; i < length; i++) { + T oa = a[i]; + T ob = b[i]; + if (oa != ob) { + // Null-value comparison is deferred to the comparator + int v = cmp.compare(oa, ob); + if (v != 0) { + return v; + } + } + } + + return a.length - b.length; + } + + /** + * Compares two {@code Object} arrays lexicographically over the specified + * ranges. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the lexicographic comparison is the result of comparing with the + * specified comparator two elements at a relative index within the + * respective arrays that is the prefix length. + * Otherwise, one array is a proper prefix of the other and, lexicographic + * comparison is the result of comparing the two range lengths. + * (See {@link #mismatch(Object[], int, int, Object[], int, int)} for the + * definition of a common and proper prefix.) + * + * @apiNote + *

This method behaves as if (for non-{@code null} array elements): + *

{@code
+     *     int i = Arrays.mismatch(a, aFromIndex, aToIndex,
+     *                             b, bFromIndex, bToIndex, cmp);
+     *     if (i >= 0 && i < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     *         return cmp.compare(a[aFromIndex + i], b[bFromIndex + i]);
+     *     return (aToIndex - aFromIndex) - (bToIndex - bFromIndex);
+     * }
+ * + * @param a the first array to compare + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be compared + * @param aToIndex the index (exclusive) of the last element in the + * first array to be compared + * @param b the second array to compare + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be compared + * @param bToIndex the index (exclusive) of the last element in the + * second array to be compared + * @param cmp the comparator to compare array elements + * @param the type of array elements + * @return the value {@code 0} if, over the specified ranges, the first and + * second array are equal and contain the same elements in the same + * order; + * a value less than {@code 0} if, over the specified ranges, the + * first array is lexicographically less than the second array; and + * a value greater than {@code 0} if, over the specified ranges, the + * first array is lexicographically greater than the second array + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array or the comparator is {@code null} + * @since 9 + */ + public static int compare( + T[] a, int aFromIndex, int aToIndex, + T[] b, int bFromIndex, int bToIndex, + Comparator cmp) { + Objects.requireNonNull(cmp); + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + T oa = a[aFromIndex++]; + T ob = b[bFromIndex++]; + if (oa != ob) { + // Null-value comparison is deferred to the comparator + int v = cmp.compare(oa, ob); + if (v != 0) { + return v; + } + } + } + + return aLength - bLength; + } + + + // Mismatch methods + + // Mismatch boolean + + /** + * Finds and returns the index of the first mismatch between two + * {@code boolean} arrays, otherwise return -1 if no mismatch is found. The + * index will be in the range of 0 (inclusive) up to the length (inclusive) + * of the smaller array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(boolean[] a, boolean[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code boolean} arrays over the specified ranges, otherwise return -1 if + * no mismatch is found. The index will be in the range of 0 (inclusive) up + * to the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(boolean[] a, int aFromIndex, int aToIndex, + boolean[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch byte + + /** + * Finds and returns the index of the first mismatch between two {@code byte} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(byte[] a, byte[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code byte} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(byte[] a, int aFromIndex, int aToIndex, + byte[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch char + + /** + * Finds and returns the index of the first mismatch between two {@code char} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(char[] a, char[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code char} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(char[] a, int aFromIndex, int aToIndex, + char[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch short + + /** + * Finds and returns the index of the first mismatch between two {@code short} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(short[] a, short[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code short} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(short[] a, int aFromIndex, int aToIndex, + short[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch int + + /** + * Finds and returns the index of the first mismatch between two {@code int} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(int[] a, int[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code int} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(int[] a, int aFromIndex, int aToIndex, + int[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch long + + /** + * Finds and returns the index of the first mismatch between two {@code long} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     a[pl] != b[pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(long[] a, long[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (a[i] != b[i]) return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code long} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     a[aFromIndex + pl] != b[bFromIndex + pl]
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(long[] a, int aFromIndex, int aToIndex, + long[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (a[aFromIndex++] != b[bFromIndex++]) return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch float + + /** + * Finds and returns the index of the first mismatch between two {@code float} + * arrays, otherwise return -1 if no mismatch is found. The index will be + * in the range of 0 (inclusive) up to the length (inclusive) of the smaller + * array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     Float.compare(a[pl], b[pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(float[] a, float[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + float va = a[i], vb = b[i]; + if (Float.floatToRawIntBits(va) != Float.floatToRawIntBits(vb)) + if (!Float.isNaN(va) || !Float.isNaN(vb)) + return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code float} arrays over the specified ranges, otherwise return -1 if no + * mismatch is found. The index will be in the range of 0 (inclusive) up to + * the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     Float.compare(a[aFromIndex + pl], b[bFromIndex + pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(float[] a, int aFromIndex, int aToIndex, + float[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + float va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Float.floatToRawIntBits(va) != Float.floatToRawIntBits(vb)) + if (!Float.isNaN(va) || !Float.isNaN(vb)) + return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch double + + /** + * Finds and returns the index of the first mismatch between two + * {@code double} arrays, otherwise return -1 if no mismatch is found. The + * index will be in the range of 0 (inclusive) up to the length (inclusive) + * of the smaller array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     Double.compare(a[pl], b[pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(double[] a, double[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + double va = a[i], vb = b[i]; + if (Double.doubleToRawLongBits(va) != Double.doubleToRawLongBits(vb)) + if (!Double.isNaN(va) || !Double.isNaN(vb)) + return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code double} arrays over the specified ranges, otherwise return -1 if + * no mismatch is found. The index will be in the range of 0 (inclusive) up + * to the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     Double.compare(a[aFromIndex + pl], b[bFromIndex + pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(double[] a, int aFromIndex, int aToIndex, + double[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + double va = a[aFromIndex++], vb = b[bFromIndex++]; + if (Double.doubleToRawLongBits(va) != Double.doubleToRawLongBits(vb)) + if (!Double.isNaN(va) || !Double.isNaN(vb)) + return i; + } + + return aLength != bLength ? length : -1; + } + + // Mismatch objects + + /** + * Finds and returns the index of the first mismatch between two + * {@code Object} arrays, otherwise return -1 if no mismatch is found. The + * index will be in the range of 0 (inclusive) up to the length (inclusive) + * of the smaller array. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     Arrays.equals(a, 0, pl, b, 0, pl) &&
+     *     !Objects.equals(a[pl], b[pl])
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     Arrays.equals(a, 0, Math.min(a.length, b.length),
+     *                   b, 0, Math.min(a.length, b.length))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch(Object[] a, Object[] b) { + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + if (!Objects.equals(a[i], b[i])) + return i; + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code Object} arrays over the specified ranges, otherwise return -1 if + * no mismatch is found. The index will be in the range of 0 (inclusive) up + * to the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, aFromIndex, aFromIndex + pl, b, bFromIndex, bFromIndex + pl) &&
+     *     !Objects.equals(a[aFromIndex + pl], b[bFromIndex + pl])
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     Arrays.equals(a, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex),
+     *                   b, 0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex))
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array is {@code null} + * @since 9 + */ + public static int mismatch( + Object[] a, int aFromIndex, int aToIndex, + Object[] b, int bFromIndex, int bToIndex) { + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + if (!Objects.equals(a[aFromIndex++], b[bFromIndex++])) + return i; + } + + return aLength != bLength ? length : -1; + } + + /** + * Finds and returns the index of the first mismatch between two + * {@code Object} arrays, otherwise return -1 if no mismatch is found. + * The index will be in the range of 0 (inclusive) up to the length + * (inclusive) of the smaller array. + * + *

The specified comparator is used to determine if two array elements + * from the each array are not equal. + * + *

If the two arrays share a common prefix then the returned index is the + * length of the common prefix and it follows that there is a mismatch + * between the two elements at that index within the respective arrays. + * If one array is a proper prefix of the other then the returned index is + * the length of the smaller array and it follows that the index is only + * valid for the larger array. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(a.length, b.length) &&
+     *     IntStream.range(0, pl).
+     *         map(i -> cmp.compare(a[i], b[i])).
+     *         allMatch(c -> c == 0) &&
+     *     cmp.compare(a[pl], b[pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b}, share a proper + * prefix if the following expression is true: + *

{@code
+     *     a.length != b.length &&
+     *     IntStream.range(0, Math.min(a.length, b.length)).
+     *         map(i -> cmp.compare(a[i], b[i])).
+     *         allMatch(c -> c == 0) &&
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param b the second array to be tested for a mismatch + * @param cmp the comparator to compare array elements + * @param the type of array elements + * @return the index of the first mismatch between the two arrays, + * otherwise {@code -1}. + * @throws NullPointerException + * if either array or the comparator is {@code null} + * @since 9 + */ + public static int mismatch(T[] a, T[] b, Comparator cmp) { + Objects.requireNonNull(cmp); + int length = Math.min(a.length, b.length); // Check null array refs + if (a == b) + return -1; + + for (int i = 0; i < length; i++) { + T oa = a[i]; + T ob = b[i]; + if (oa != ob) { + // Null-value comparison is deferred to the comparator + int v = cmp.compare(oa, ob); + if (v != 0) { + return i; + } + } + } + + return a.length != b.length ? length : -1; + } + + /** + * Finds and returns the relative index of the first mismatch between two + * {@code Object} arrays over the specified ranges, otherwise return -1 if + * no mismatch is found. The index will be in the range of 0 (inclusive) up + * to the length (inclusive) of the smaller range. + * + *

If the two arrays, over the specified ranges, share a common prefix + * then the returned relative index is the length of the common prefix and + * it follows that there is a mismatch between the two elements at that + * relative index within the respective arrays. + * If one array is a proper prefix of the other, over the specified ranges, + * then the returned relative index is the length of the smaller range and + * it follows that the relative index is only valid for the array with the + * larger range. + * Otherwise, there is no mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a common + * prefix of length {@code pl} if the following expression is true: + *

{@code
+     *     pl >= 0 &&
+     *     pl < Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex) &&
+     *     IntStream.range(0, pl).
+     *         map(i -> cmp.compare(a[aFromIndex + i], b[bFromIndex + i])).
+     *         allMatch(c -> c == 0) &&
+     *     cmp.compare(a[aFromIndex + pl], b[bFromIndex + pl]) != 0
+     * }
+ * Note that a common prefix length of {@code 0} indicates that the first + * elements from each array mismatch. + * + *

Two non-{@code null} arrays, {@code a} and {@code b} with specified + * ranges [{@code aFromIndex}, {@code atoIndex}) and + * [{@code bFromIndex}, {@code btoIndex}) respectively, share a proper + * if the following expression is true: + *

{@code
+     *     (aToIndex - aFromIndex) != (bToIndex - bFromIndex) &&
+     *     IntStream.range(0, Math.min(aToIndex - aFromIndex, bToIndex - bFromIndex)).
+     *         map(i -> cmp.compare(a[aFromIndex + i], b[bFromIndex + i])).
+     *         allMatch(c -> c == 0)
+     * }
+ * + * @param a the first array to be tested for a mismatch + * @param aFromIndex the index (inclusive) of the first element in the + * first array to be tested + * @param aToIndex the index (exclusive) of the last element in the + * first array to be tested + * @param b the second array to be tested for a mismatch + * @param bFromIndex the index (inclusive) of the first element in the + * second array to be tested + * @param bToIndex the index (exclusive) of the last element in the + * second array to be tested + * @param cmp the comparator to compare array elements + * @param the type of array elements + * @return the relative index of the first mismatch between the two arrays + * over the specified ranges, otherwise {@code -1}. + * @throws IllegalArgumentException + * if {@code aFromIndex > aToIndex} or + * if {@code bFromIndex > bToIndex} + * @throws ArrayIndexOutOfBoundsException + * if {@code aFromIndex < 0 or aToIndex > a.length} or + * if {@code bFromIndex < 0 or bToIndex > b.length} + * @throws NullPointerException + * if either array or the comparator is {@code null} + * @since 9 + */ + public static int mismatch( + T[] a, int aFromIndex, int aToIndex, + T[] b, int bFromIndex, int bToIndex, + Comparator cmp) { + Objects.requireNonNull(cmp); + rangeCheck(a.length, aFromIndex, aToIndex); + rangeCheck(b.length, bFromIndex, bToIndex); + + int aLength = aToIndex - aFromIndex; + int bLength = bToIndex - bFromIndex; + int length = Math.min(aLength, bLength); + for (int i = 0; i < length; i++) { + T oa = a[aFromIndex++]; + T ob = b[bFromIndex++]; + if (oa != ob) { + // Null-value comparison is deferred to the comparator + int v = cmp.compare(oa, ob); + if (v != 0) { + return i; + } + } + } + + return aLength != bLength ? length : -1; + } +} \ No newline at end of file