/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.lang.reflect;
/**
* This class provides static methods to create and access arrays dynamically.
*/
public final class Array {
/**
* Prevent this class from being instantiated.
*/
private Array(){
//do nothing
}
/**
* Returns the length of the array. This reproduces the effect of {@code
* array.length}
*
* @param array
* the array
* @return the length of the array
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array
*/
public static int getLength(Object array) {
if (array == null) {
throw new NullPointerException();
}
if (!array.getClass().isArray()) {
throw new IllegalArgumentException(array.getClass()+" is not an array");
}
return getLength2(array);
}
private static native int getLength2(Object array) /*-{
return array.length;
}-*/;
/**
* Returns a new array of the specified component type and length. This
* reproduces the effect of {@code new componentType[size]}.
*
* @param componentType
* the component type of the new array
* @param size
* the length of the new array
* @return the new array
* @throws NullPointerException
* if the component type is null
* @throws NegativeArraySizeException
* if {@code size < 0}
*/
public static Object newInstance(Class<?> componentType, int length)
throws NegativeArraySizeException {
if (componentType == null) {
throw new NullPointerException();
}
if (length < 0) {
throw new NegativeArraySizeException(String.valueOf(length));
}
if (componentType == boolean.class) {
return new boolean[length];
}
if (componentType == byte.class) {
return new byte[length];
}
if (componentType == char.class) {
return new char[length];
}
if (componentType == short.class) {
return new short[length];
}
if (componentType == int.class) {
return new int[length];
}
if (componentType == long.class) {
return new long[length];
}
if (componentType == float.class) {
return new float[length];
}
if (componentType == double.class) {
return new double[length];
}
return new Object[length];
}
/**
* Returns the element of the array at the specified index. This reproduces
* the effect of {@code array[index]}. If the array component is a primitive
* type, the result is automatically wrapped.
*
* @param array
* the array
* @param index
* the index
* @return the requested element, possibly wrapped
* @throws NullPointerException
* if the array is null
* @throws IllegalArgumentException
* if {@code array} is not an array
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static Object get(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
if (array == null) {
throw new NullPointerException();
}
if (!array.getClass().isArray()) {
throw new IllegalArgumentException(array.getClass()+" is not an array");
}
if ((index < 0) || (index >= getLength2(array))) {
throw new ArrayIndexOutOfBoundsException(String.valueOf(index));
}
return get2(array, index);
}
private static native Object get2(Object array, int index) /*-{
return array[index];
}-*/;
/**
* Sets the element of the array at the specified index to the value. This
* reproduces the effect of {@code array[index] = value}. If the array
* component is a primitive type, the value is automatically unwrapped.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
*
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void set(Object array, int index, Object value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
if (array == null) {
throw new NullPointerException();
}
if (!array.getClass().isArray()) {
throw new IllegalArgumentException(array.getClass()+" is not an array");
}
if ((index < 0) || (index >= getLength2(array))) {
throw new ArrayIndexOutOfBoundsException(String.valueOf(index));
}
set2(array, index, value);
}
private static native void set2(Object array, int index, Object value) /*-{
array[index] = value;
}-*/;
/**
* Returns the element of the array at the specified index, converted to a
* {@code boolean}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static boolean getBoolean(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((boolean[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code byte}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static byte getByte(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((byte[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code char}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static char getChar(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((char[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code double}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static double getDouble(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((double[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code float}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static float getFloat(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((float[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to an
* {@code int}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static int getInt(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((int[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code long}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static long getLong(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((long[]) array)[index];
}
/**
* Returns the element of the array at the specified index, converted to a
* {@code short}, if possible. This reproduces the effect of {@code
* array[index]}
*
* @param array
* the array
* @param index
* the index
* @return the requested element
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if {@code array} is not an array or the element at the
* index position can not be converted to the return type
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static short getShort(Object array, int index)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
return ((short[]) array)[index];
}
/**
* Sets the element of the array at the specified index to the {@code
* boolean} value. This reproduces the effect of {@code array[index] =
* value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
*
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setBoolean(Object array, int index, boolean value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((boolean[]) array)[index] = value;
}
/**
* Sets the element of the array at the specified index to the {@code byte}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setByte(Object array, int index, byte value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((byte[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code char}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setChar(Object array, int index, char value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((char[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code double}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setDouble(Object array, int index, double value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((double[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code float}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setFloat(Object array, int index, float value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((float[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code int}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setInt(Object array, int index, int value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((int[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code long}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setLong(Object array, int index, long value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((long[]) array)[index] = value;
}
/**
* Set the element of the array at the specified index to the {@code short}
* value. This reproduces the effect of {@code array[index] = value}.
*
* @param array
* the array
* @param index
* the index
* @param value
* the new value
* @throws NullPointerException
* if the {@code array} is {@code null}
* @throws IllegalArgumentException
* if the {@code array} is not an array or the value cannot be
* converted to the array type by a widening conversion
* @throws ArrayIndexOutOfBoundsException
* if {@code index < 0 || index >= array.length}
*/
public static void setShort(Object array, int index, short value)
throws IllegalArgumentException, ArrayIndexOutOfBoundsException {
((short[]) array)[index] = value;
}
}