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/*
* 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 org.apache.commons.collections4;
/**
*
* Operations on arrays, primitive arrays (like {@code int[]}) and primitive wrapper arrays (like {@code Integer[]}).
*
*
* This class tries to handle {@code null} input gracefully. An exception will not be thrown for a {@code null} array
* input. However, an Object array that contains a {@code null} element may throw an exception. Each method documents
* its behaviour.
*
*
* Package private, might move to an internal package if this needs to be public.
*
*
* #ThreadSafe#
*
*
* @since 4.2 (Copied from Apache Commons Lang.)
*
*/
class ArrayUtils {
/**
* The index value when an element is not found in a list or array: {@code -1}. This value is returned by methods in
* this class and can also be used in comparisons with values returned by various method from
* {@link java.util.List}.
*/
static final int INDEX_NOT_FOUND = -1;
/**
*
* Checks if the object is in the given array.
*
*
*
* The method returns {@code false} if a {@code null} array is passed in.
*
*
* @param array
* the array to search through
* @param objectToFind
* the object to find
* @return {@code true} if the array contains the object
*/
static boolean contains(final Object[] array, final Object objectToFind) {
return indexOf(array, objectToFind) != INDEX_NOT_FOUND;
}
/**
*
* Finds the index of the given object in the array.
*
*
*
* This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array.
*
*
* @param array
* the array to search through for the object, may be {@code null}
* @param objectToFind
* the object to find, may be {@code null}
* @return the index of the object within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or
* {@code null} array input
*/
static int indexOf(final T[] array, final Object objectToFind) {
return indexOf(array, objectToFind, 0);
}
/**
*
* Finds the index of the given object in the array starting at the given index.
*
*
*
* This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array.
*
*
*
* A negative startIndex is treated as zero. A startIndex larger than the array length will return
* {@link #INDEX_NOT_FOUND} ({@code -1}).
*
*
* @param array
* the array to search through for the object, may be {@code null}
* @param objectToFind
* the object to find, may be {@code null}
* @param startIndex
* the index to start searching at
* @return the index of the object within the array starting at the index, {@link #INDEX_NOT_FOUND} ({@code -1}) if
* not found or {@code null} array input
*/
static int indexOf(final Object[] array, final Object objectToFind, int startIndex) {
if (array == null) {
return INDEX_NOT_FOUND;
}
if (startIndex < 0) {
startIndex = 0;
}
if (objectToFind == null) {
for (int i = startIndex; i < array.length; i++) {
if (array[i] == null) {
return i;
}
}
} else {
for (int i = startIndex; i < array.length; i++) {
if (objectToFind.equals(array[i])) {
return i;
}
}
}
return INDEX_NOT_FOUND;
}
}