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import java.lang.reflect.Array;
/*
* 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.
*
*
*/
/**
* @author Stephen Colebourne
* @author Moritz Petersen
* @author <a href="mailto:fredrik@westermarck.com">Fredrik Westermarck</a>
* @author Nikolay Metchev
* @author Matthew Hawthorne
* @author Tim O'Brien
* @author Pete Gieser
* @author Gary Gregory
* @author <a href="mailto:equinus100@hotmail.com">Ashwin S</a>
* @author Maarten Coene
* @since 2.0
* @version $Id: ArrayUtils.java 632503 2008-03-01 00:21:52Z ggregory $
*/
public class Main {
// Subarrays
//-----------------------------------------------------------------------
/**
* Produces a new array containing the elements between
* the start and end indices.
*
* The start index is inclusive, the end index exclusive.
* Null array input produces null output.
*
* The component type of the subarray is always the same as
* that of the input array. Thus, if the input is an array of type
* <code>Date</code>, the following usage is envisaged:
*
* <pre>
* Date[] someDates = (Date[])ArrayUtils.subarray(allDates, 2, 5);
* </pre>
*
* @param array the array
* @param startIndexInclusive the starting index. Undervalue (<0)
* is promoted to 0, overvalue (>array.length) results
* in an empty array.
* @param endIndexExclusive elements up to endIndex-1 are present in the
* returned subarray. Undervalue (< startIndex) produces
* empty array, overvalue (>array.length) is demoted to
* array length.
* @return a new array containing the elements between
* the start and end indices.
* @since 2.1
*/
public static Object[] subarray(Object[] array, int startIndexInclusive, int endIndexExclusive) {
if (array == null) {
return null;
}
if (startIndexInclusive < 0) {
startIndexInclusive = 0;
}
if (endIndexExclusive > array.length) {
endIndexExclusive = array.length;
}
int newSize = endIndexExclusive - startIndexInclusive;
Class type = array.getClass().getComponentType();
if (newSize <= 0) {
return (Object[]) Array.newInstance(type, 0);
}
Object[] subarray = (Object[]) Array.newInstance(type, newSize);
System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
return subarray;
}
}
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