jdk/src/share/classes/java/lang/reflect/Array.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/lang/reflect/Array.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,485 @@
+/*
+ * Copyright 1996-2006 Sun Microsystems, 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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+package java.lang.reflect;
+
+/**
+ * The {@code Array} class provides static methods to dynamically create and
+ * access Java arrays.
+ *
+ * <p>{@code Array} permits widening conversions to occur during a get or set
+ * operation, but throws an {@code IllegalArgumentException} if a narrowing
+ * conversion would occur.
+ *
+ * @author Nakul Saraiya
+ */
+public final
+class Array {
+
+    /**
+     * Constructor.  Class Array is not instantiable.
+     */
+    private Array() {}
+
+    /**
+     * Creates a new array with the specified component type and
+     * length.
+     * Invoking this method is equivalent to creating an array
+     * as follows:
+     * <blockquote>
+     * <pre>
+     * int[] x = {length};
+     * Array.newInstance(componentType, x);
+     * </pre>
+     * </blockquote>
+     *
+     * @param componentType the {@code Class} object representing the
+     * component type of the new array
+     * @param length the length of the new array
+     * @return the new array
+     * @exception NullPointerException if the specified
+     * {@code componentType} parameter is null
+     * @exception IllegalArgumentException if componentType is {@link Void#TYPE}
+     * @exception NegativeArraySizeException if the specified {@code length}
+     * is negative
+     */
+    public static Object newInstance(Class<?> componentType, int length)
+        throws NegativeArraySizeException {
+        return newArray(componentType, length);
+    }
+
+    /**
+     * Creates a new array
+     * with the specified component type and dimensions.
+     * If {@code componentType}
+     * represents a non-array class or interface, the new array
+     * has {@code dimensions.length} dimensions and
+     * {@code componentType} as its component type. If
+     * {@code componentType} represents an array class, the
+     * number of dimensions of the new array is equal to the sum
+     * of {@code dimensions.length} and the number of
+     * dimensions of {@code componentType}. In this case, the
+     * component type of the new array is the component type of
+     * {@code componentType}.
+     *
+     * <p>The number of dimensions of the new array must not
+     * exceed the number of array dimensions supported by the
+     * implementation (typically 255).
+     *
+     * @param componentType the {@code Class} object representing the component
+     * type of the new array
+     * @param dimensions an array of {@code int} representing the dimensions of
+     * the new array
+     * @return the new array
+     * @exception NullPointerException if the specified
+     * {@code componentType} argument is null
+     * @exception IllegalArgumentException if the specified {@code dimensions}
+     * argument is a zero-dimensional array, or if the number of
+     * requested dimensions exceeds the limit on the number of array dimensions
+     * supported by the implementation (typically 255), or if componentType
+     * is {@link Void#TYPE}.
+     * @exception NegativeArraySizeException if any of the components in
+     * the specified {@code dimensions} argument is negative.
+     */
+    public static Object newInstance(Class<?> componentType, int... dimensions)
+        throws IllegalArgumentException, NegativeArraySizeException {
+        return multiNewArray(componentType, dimensions);
+    }
+
+    /**
+     * Returns the length of the specified array object, as an {@code int}.
+     *
+     * @param array the array
+     * @return the length of the array
+     * @exception IllegalArgumentException if the object argument is not
+     * an array
+     */
+    public static native int getLength(Object array)
+        throws IllegalArgumentException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object.  The value is automatically wrapped in an object
+     * if it has a primitive type.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the (possibly wrapped) value of the indexed component in
+     * the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     */
+    public static native Object get(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code boolean}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native boolean getBoolean(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code byte}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native byte getByte(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code char}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native char getChar(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code short}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native short getShort(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as an {@code int}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native int getInt(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code long}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native long getLong(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code float}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native float getFloat(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Returns the value of the indexed component in the specified
+     * array object, as a {@code double}.
+     *
+     * @param array the array
+     * @param index the index
+     * @return the value of the indexed component in the specified array
+     * @exception NullPointerException If the specified object is null
+     * @exception IllegalArgumentException If the specified object is not
+     * an array, or if the indexed element cannot be converted to the
+     * return type by an identity or widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to the
+     * length of the specified array
+     * @see Array#get
+     */
+    public static native double getDouble(Object array, int index)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified new value.  The new value is first
+     * automatically unwrapped if the array has a primitive component
+     * type.
+     * @param array the array
+     * @param index the index into the array
+     * @param value the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the array component type is primitive and
+     * an unwrapping conversion fails
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     */
+    public static native void set(Object array, int index, Object value)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code boolean} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param z the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setBoolean(Object array, int index, boolean z)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code byte} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param b the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setByte(Object array, int index, byte b)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code char} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param c the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setChar(Object array, int index, char c)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code short} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param s the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setShort(Object array, int index, short s)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code int} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param i the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setInt(Object array, int index, int i)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code long} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param l the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setLong(Object array, int index, long l)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code float} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param f the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setFloat(Object array, int index, float f)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /**
+     * Sets the value of the indexed component of the specified array
+     * object to the specified {@code double} value.
+     * @param array the array
+     * @param index the index into the array
+     * @param d the new value of the indexed component
+     * @exception NullPointerException If the specified object argument
+     * is null
+     * @exception IllegalArgumentException If the specified object argument
+     * is not an array, or if the specified value cannot be converted
+     * to the underlying array's component type by an identity or a
+     * primitive widening conversion
+     * @exception ArrayIndexOutOfBoundsException If the specified {@code index}
+     * argument is negative, or if it is greater than or equal to
+     * the length of the specified array
+     * @see Array#set
+     */
+    public static native void setDouble(Object array, int index, double d)
+        throws IllegalArgumentException, ArrayIndexOutOfBoundsException;
+
+    /*
+     * Private
+     */
+
+    private static native Object newArray(Class componentType, int length)
+        throws NegativeArraySizeException;
+
+    private static native Object multiNewArray(Class componentType,
+        int[] dimensions)
+        throws IllegalArgumentException, NegativeArraySizeException;
+
+
+}