/* Copyright 2004 The Apache Software Foundation
*
* Licensed 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.
*/
import java.lang.reflect.Array;
/**
* Operations on arrays, primitive arrays (like int[]) and
* primitive wrapper arrays (like Integer[]).
*
* This class tries to handle null input gracefully.
* An exception will not be thrown for a null
* array input. However, an Object array that contains a null
* element may throw an exception. Each method documents its behaviour.
*
* @author Stephen Colebourne
* @author Moritz Petersen
* @author Fredrik Westermarck
* @author Nikolay Metchev
* @author Matthew Hawthorne
* @author Tim O'Brien
* @author Pete Gieser
* @author Gary Gregory
* @author Ashwin S
* @author Maarten Coene
* @since 2.0
* @version $Id: ArrayUtils.java 632503 2008-03-01 00:21:52Z ggregory $
*/
public class Main {
/**
* Copies the given array and adds the given element at the end of the new array.
*
* The new array contains the same elements of the input
* array plus the given element in the last position. The component type of
* the new array is the same as that of the input array.
*
* If the input array is null, a new one element array is returned
* whose component type is the same as the element.
*
*
* ArrayUtils.add(null, null) = [null]
* ArrayUtils.add(null, "a") = ["a"]
* ArrayUtils.add(["a"], null) = ["a", null]
* ArrayUtils.add(["a"], "b") = ["a", "b"]
* ArrayUtils.add(["a", "b"], "c") = ["a", "b", "c"]
*
*
* @param array the array to "add" the element to, may be null
* @param element the object to add
* @return A new array containing the existing elements plus the new element
* @since 2.1
*/
public static Object[] add(Object[] array, Object element) {
Class type = array != null ? array.getClass() : (element != null ? element.getClass() : Object.class);
Object[] newArray = (Object[]) copyArrayGrow1(array, type);
newArray[newArray.length - 1] = element;
return newArray;
}
/**
* Returns a copy of the given array of size 1 greater than the argument.
* The last value of the array is left to the default value.
*
* @param array The array to copy, must not be null.
* @param newArrayComponentType If array is null, create a
* size 1 array of this type.
* @return A new copy of the array of size 1 greater than the input.
*/
private static Object copyArrayGrow1(Object array, Class newArrayComponentType) {
if (array != null) {
int arrayLength = Array.getLength(array);
Object newArray = Array.newInstance(array.getClass().getComponentType(), arrayLength + 1);
System.arraycopy(array, 0, newArray, 0, arrayLength);
return newArray;
}
return Array.newInstance(newArrayComponentType, 1);
}
}