/*

  * Copyright (c) 1996, 2006, Oracle and/or its affiliates. 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.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package java.lang.reflect;

 import org.apidesign.bck2brwsr.core.JavaScriptBody;

 import org.apidesign.bck2brwsr.core.JavaScriptPrototype;

 /**

  * 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

  */

 @JavaScriptPrototype(prototype = "new Array", container = "Array.prototype")

 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 {

         if (length < 0) {

             throw new NegativeArraySizeException();

         }

         String sig = findSignature(componentType);

         return newArray(componentType.isPrimitive(), sig, length);

     }

     private static String findSignature(Class<?> type) {

         if (type == Integer.TYPE) {

             return "[I";

         }

         if (type == Long.TYPE) {

             return "[J";

         }

         if (type == Double.TYPE) {

             return "[D";

         }

         if (type == Float.TYPE) {

             return "[F";

         }

         if (type == Byte.TYPE) {

             return "[B";

         }

         if (type == Boolean.TYPE) {

             return "[Z";

         }

         if (type == Short.TYPE) {

             return "[S";

         }

         if (type == Character.TYPE) {

             return "[C";

         }

         if (type.getName().equals("void")) {

             throw new IllegalStateException("Can't create array for " + type);

         }

         return "[L" + type.getName() + ";";

     }

     /**

      * 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 {

         StringBuilder sig = new StringBuilder();

         for (int i = 1; i < dimensions.length; i++) {

             sig.append('[');

         }

         sig.append(findSignature(componentType));

         return multiNewArray(sig.toString(), dimensions, 0);

     }

     /**

      * 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 int getLength(Object array)

     throws IllegalArgumentException {

         if (!array.getClass().isArray()) {

             throw new IllegalArgumentException("Argument is not an array");

         }

         return length(array);

     }

     @JavaScriptBody(args = { "arr" }, body = "return arr.length;")

     private static native int length(Object arr);

     /**

      * 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 byte getByte(Object array, int index)

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         if (array.getClass().getComponentType() != Byte.TYPE) {

             throw new IllegalArgumentException();

         }

         byte[] arr = (byte[]) array;

         return arr[index];

     }

     /**

      * 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 short getShort(Object array, int index)

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         final Class<?> t = array.getClass().getComponentType();

         if (t == Short.TYPE) {

             short[] arr = (short[]) array;

             return arr[index];

         }

         return getByte(array, index);

     }

     /**

      * 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 int getInt(Object array, int index) 

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         final Class<?> t = array.getClass().getComponentType();

         if (t == Integer.TYPE) {

             int[] arr = (int[]) array;

             return arr[index];

         }

         return getShort(array, index);

     }

     /**

      * 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 long getLong(Object array, int index)

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         final Class<?> t = array.getClass().getComponentType();

         if (t == Long.TYPE) {

             long[] arr = (long[]) array;

             return arr[index];

         }

         return getInt(array, index);

     }

     /**

      * 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 float getFloat(Object array, int index)

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         final Class<?> t = array.getClass().getComponentType();

         if (t == Float.TYPE) {

             float[] arr = (float[]) array;

             return arr[index];

         }

         return getLong(array, index);

     }

     /**

      * 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 double getDouble(Object array, int index)

     throws IllegalArgumentException, ArrayIndexOutOfBoundsException {

         final Class<?> t = array.getClass().getComponentType();

         if (t == Double.TYPE) {

             double[] arr = (double[]) array;

             return arr[index];

         }

         return getFloat(array, index);

     }

     /**

      * 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

      */

     @JavaScriptBody(args = { "primitive", "sig", "length" }, body =

           "var arr = new Array(length);\n"

         + "var value = primitive ? 0 : null;\n"

         + "for(var i = 0; i < length; i++) arr[i] = value;\n"

         + "arr.jvmName = sig;\n"

         + "return arr;"

     )

     private static native Object newArray(boolean primitive, String sig, int length);

     private static Object multiNewArray(String sig, int[] dims, int index)

     throws IllegalArgumentException, NegativeArraySizeException {

         if (dims.length == index + 1) {

             return newArray(sig.length() == 2, sig, dims[index]);

         }

         Object[] arr = (Object[]) newArray(false, sig, dims[index]);

         String compsig = sig.substring(1);

         for (int i = 0; i < arr.length; i++) {

             arr[i] = multiNewArray(compsig, dims, index + 1);

         }

         return arr;

     }

 }