6582946: Add suite of compare(T, T) methods for ints, longs etc
authormartin
Tue, 22 Sep 2009 18:30:58 -0700
changeset 3943 11abf5578222
parent 3942 685e04a98396
child 3944 e098e010b520
6582946: Add suite of compare(T, T) methods for ints, longs etc Reviewed-by: darcy Contributed-by: kevinb@google.com
jdk/src/share/classes/java/lang/Boolean.java
jdk/src/share/classes/java/lang/Byte.java
jdk/src/share/classes/java/lang/Character.java
jdk/src/share/classes/java/lang/Integer.java
jdk/src/share/classes/java/lang/Long.java
jdk/src/share/classes/java/lang/Short.java
jdk/test/java/lang/Compare.java
--- a/jdk/src/share/classes/java/lang/Boolean.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Boolean.java	Tue Sep 22 18:30:58 2009 -0700
@@ -255,7 +255,25 @@
      * @since  1.5
      */
     public int compareTo(Boolean b) {
-        return (b.value == value ? 0 : (value ? 1 : -1));
+        return compare(this.value, b.value);
+    }
+
+    /**
+     * Compares two {@code boolean} values.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code boolean} to compare
+     * @param  y the second {@code boolean} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code !x && y}; and
+     *         a value greater than {@code 0} if {@code x && !y}
+     * @since 1.7
+     */
+    public static int compare(boolean x, boolean y) {
+        return (x == y) ? 0 : (x ? 1 : -1);
     }
 
     private static boolean toBoolean(String name) {
--- a/jdk/src/share/classes/java/lang/Byte.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Byte.java	Tue Sep 22 18:30:58 2009 -0700
@@ -418,7 +418,25 @@
      * @since   1.2
      */
     public int compareTo(Byte anotherByte) {
-        return this.value - anotherByte.value;
+        return compare(this.value, anotherByte.value);
+    }
+
+    /**
+     * Compares two {@code byte} values numerically.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Byte.valueOf(x).compareTo(Byte.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code byte} to compare
+     * @param  y the second {@code byte} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code x < y}; and
+     *         a value greater than {@code 0} if {@code x > y}
+     * @since 1.7
+     */
+    public static int compare(byte x, byte y) {
+        return x - y;
     }
 
     /**
--- a/jdk/src/share/classes/java/lang/Character.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Character.java	Tue Sep 22 18:30:58 2009 -0700
@@ -4964,7 +4964,25 @@
      * @since   1.2
      */
     public int compareTo(Character anotherCharacter) {
-        return this.value - anotherCharacter.value;
+        return compare(this.value, anotherCharacter.value);
+    }
+
+    /**
+     * Compares two {@code char} values numerically.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Character.valueOf(x).compareTo(Character.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code char} to compare
+     * @param  y the second {@code char} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code x < y}; and
+     *         a value greater than {@code 0} if {@code x > y}
+     * @since 1.7
+     */
+    public static int compare(char x, char y) {
+        return x - y;
     }
 
     /**
--- a/jdk/src/share/classes/java/lang/Integer.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Integer.java	Tue Sep 22 18:30:58 2009 -0700
@@ -1010,9 +1010,25 @@
      * @since   1.2
      */
     public int compareTo(Integer anotherInteger) {
-        int thisVal = this.value;
-        int anotherVal = anotherInteger.value;
-        return (thisVal<anotherVal ? -1 : (thisVal==anotherVal ? 0 : 1));
+        return compare(this.value, anotherInteger.value);
+    }
+
+    /**
+     * Compares two {@code int} values numerically.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Integer.valueOf(x).compareTo(Integer.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code int} to compare
+     * @param  y the second {@code int} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code x < y}; and
+     *         a value greater than {@code 0} if {@code x > y}
+     * @since 1.7
+     */
+    public static int compare(int x, int y) {
+        return (x < y) ? -1 : ((x == y) ? 0 : 1);
     }
 
 
--- a/jdk/src/share/classes/java/lang/Long.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Long.java	Tue Sep 22 18:30:58 2009 -0700
@@ -950,9 +950,25 @@
      * @since   1.2
      */
     public int compareTo(Long anotherLong) {
-        long thisVal = this.value;
-        long anotherVal = anotherLong.value;
-        return (thisVal<anotherVal ? -1 : (thisVal==anotherVal ? 0 : 1));
+        return compare(this.value, anotherLong.value);
+    }
+
+    /**
+     * Compares two {@code long} values numerically.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Long.valueOf(x).compareTo(Long.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code long} to compare
+     * @param  y the second {@code long} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code x < y}; and
+     *         a value greater than {@code 0} if {@code x > y}
+     * @since 1.7
+     */
+    public static int compare(long x, long y) {
+        return (x < y) ? -1 : ((x == y) ? 0 : 1);
     }
 
 
--- a/jdk/src/share/classes/java/lang/Short.java	Tue Sep 22 18:30:58 2009 -0700
+++ b/jdk/src/share/classes/java/lang/Short.java	Tue Sep 22 18:30:58 2009 -0700
@@ -423,7 +423,25 @@
      * @since   1.2
      */
     public int compareTo(Short anotherShort) {
-        return this.value - anotherShort.value;
+        return compare(this.value, anotherShort.value);
+    }
+
+    /**
+     * Compares two {@code short} values numerically.
+     * The value returned is identical to what would be returned by:
+     * <pre>
+     *    Short.valueOf(x).compareTo(Short.valueOf(y))
+     * </pre>
+     *
+     * @param  x the first {@code short} to compare
+     * @param  y the second {@code short} to compare
+     * @return the value {@code 0} if {@code x == y};
+     *         a value less than {@code 0} if {@code x < y}; and
+     *         a value greater than {@code 0} if {@code x > y}
+     * @since 1.7
+     */
+    public static int compare(short x, short y) {
+        return x - y;
     }
 
     /**
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/Compare.java	Tue Sep 22 18:30:58 2009 -0700
@@ -0,0 +1,142 @@
+/*
+ * Copyright 2009 Google, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6582946
+ * @summary Test the primitive wrappers compare and compareTo methods
+ */
+
+import java.util.Random;
+
+public class Compare {
+
+    final Random rnd = new Random();
+
+    boolean toBoolean(long x) { return x > 0; }
+
+    void compareAll(long x, long y) {
+        check(Double.compare(x, y) ==
+              Double.valueOf(x).compareTo(Double.valueOf(y)));
+        check(Float.compare(x, y) ==
+              Float.valueOf(x).compareTo(Float.valueOf(y)));
+        check(Long.compare(x, y) ==
+              Long.valueOf(x).compareTo(Long.valueOf(y)));
+        check(Integer.compare((int) x, (int) y) ==
+              Integer.valueOf((int) x).compareTo(Integer.valueOf((int) y)));
+        check(Short.compare((short) x, (short) y) ==
+              Short.valueOf((short) x).compareTo(Short.valueOf((short) y)));
+        check(Character.compare((char) x, (char) y) ==
+              Character.valueOf((char) x).compareTo(Character.valueOf((char) y)));
+        check(Byte.compare((byte) x, (byte) y) ==
+              Byte.valueOf((byte) x).compareTo(Byte.valueOf((byte) y)));
+        check(Boolean.compare(toBoolean(x), toBoolean(y)) ==
+              Boolean.valueOf(toBoolean(x)).compareTo(Boolean.valueOf(toBoolean(y))));
+
+        check(Double.compare(x, y) == -Double.compare(y, x));
+        check(Float.compare(x, y) == -Float.compare(y, x));
+        check(Long.compare(x, y) == -Long.compare(y, x));
+        check(Integer.compare((int) x, (int) y) ==
+              -Integer.compare((int) y, (int) x));
+        check(Short.compare((short) x, (short) y) ==
+              -Short.compare((short) y, (short) x));
+        check(Character.compare((char) x, (char) y) ==
+              -Character.compare((char) y, (char) x));
+        check(Byte.compare((byte) x, (byte) y) ==
+              -Byte.compare((byte) y, (byte) x));
+
+        equal(Long.compare(x, y),
+              x < y ? -1 : x > y ? 1 : 0);
+
+        {
+            int a = (int) x, b = (int) y;
+            equal(Integer.compare(a, b),
+                  a < b ? -1 : a > b ? 1 : 0);
+        }
+
+        {
+            short a = (short) x, b = (short) y;
+            equal(Short.compare(a, b),
+                  a - b);
+        }
+
+        {
+            char a = (char) x, b = (char) y;
+            equal(Character.compare(a, b),
+                  a - b);
+        }
+
+        {
+            byte a = (byte) x, b = (byte) y;
+            equal(Byte.compare(a, b),
+                  a - b);
+        }
+
+        {
+            boolean a = toBoolean(x), b = toBoolean(y);
+            equal(Boolean.compare(a, b),
+                  a == b ? 0 : a ? 1 : -1);
+        }
+    }
+
+    void test(String args[]) throws Exception {
+        long[] longs = {
+            Long.MIN_VALUE,
+            Integer.MIN_VALUE,
+            Short.MIN_VALUE,
+            Character.MIN_VALUE,
+            Byte.MIN_VALUE,
+            -1, 0, 1,
+            Byte.MAX_VALUE,
+            Character.MAX_VALUE,
+            Short.MAX_VALUE,
+            Integer.MAX_VALUE,
+            Long.MAX_VALUE,
+            rnd.nextLong(),
+            rnd.nextInt(),
+        };
+
+        for (long x : longs) {
+            for (long y : longs) {
+                compareAll(x, y);
+            }
+        }
+    }
+
+    //--------------------- Infrastructure ---------------------------
+    volatile int passed = 0, failed = 0;
+    void pass() {passed++;}
+    void fail() {failed++; Thread.dumpStack();}
+    void fail(String msg) {System.err.println(msg); fail();}
+    void unexpected(Throwable t) {failed++; t.printStackTrace();}
+    void check(boolean cond) {if (cond) pass(); else fail();}
+    void equal(Object x, Object y) {
+        if (x == null ? y == null : x.equals(y)) pass();
+        else fail(x + " not equal to " + y);}
+    public static void main(String[] args) throws Throwable {
+        new Compare().instanceMain(args);}
+    public void instanceMain(String[] args) throws Throwable {
+        try {test(args);} catch (Throwable t) {unexpected(t);}
+        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
+        if (failed > 0) throw new AssertionError("Some tests failed");}
+}