com.azure.cosmos.implementation.apachecommons.lang.ArrayUtils Maven / Gradle / Ivy
Show all versions of azure-cosmos Show documentation
/*
* 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.
*/
/*
* Portions Copyright (c) Microsoft Corporation
*/
package com.azure.cosmos.implementation.apachecommons.lang;
import java.lang.reflect.Array;
public class ArrayUtils {
/**
* An empty immutable {@code String} array.
*/
public static final String[] EMPTY_STRING_ARRAY = new String[0];
/**
* 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}.
*/
public static final int INDEX_NOT_FOUND = -1;
private ArrayUtils() {
super();
}
/**
* Returns the length of the specified array.
* This method can deal with {@code Object} arrays and with primitive arrays.
*
*
If the input array is {@code null}, {@code 0} is returned.
*
* @param array the array to retrieve the length from, may be null
* @return The length of the array, or {@code 0} if the array is {@code null}
* @throws IllegalArgumentException if the object argument is not an array.
*/
public static int getLength(final Object array) {
if (array == null) {
return 0;
}
return Array.getLength(array);
}
/**
*
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
*/
public static int indexOf(final Object[] 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
*/
public 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;
}
/**
*
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
*/
public static boolean contains(final Object[] array, final Object objectToFind) {
return indexOf(array, objectToFind) != INDEX_NOT_FOUND;
}
// ----------------------------------------------------------------------
/**
*
Checks if an array of Objects is empty or {@code null}.
*
* @param array the array to test
* @return {@code true} if the array is empty or {@code null}
*/
public static boolean isEmpty(final Object[] array) {
return getLength(array) == 0;
}
/**
*
Checks if an array of primitive chars is empty or {@code null}.
*
* @param array the array to test
* @return {@code true} if the array is empty or {@code null}
*/
public static boolean isEmpty(final char[] array) {
return getLength(array) == 0;
}
/**
*
Copies the given array and adds the given element at the end of the new array.
*
* @param the component type of the array
* @param array the array to "add" the element to, may be {@code null}
* @param element the object to add, may be {@code null}
* @return A new array containing the existing elements plus the new element
* @throws IllegalArgumentException if both arguments are null
*/
public static T[] add(final T[] array, final T element) {
Class type;
if (array != null) {
type = array.getClass().getComponentType();
} else if (element != null) {
type = element.getClass();
} else {
throw new IllegalArgumentException("Arguments cannot both be null");
}
@SuppressWarnings("unchecked") // type must be T
final
T[] newArray = (T[]) 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 {@code null}.
* @param newArrayComponentType If {@code array} is {@code 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(final Object array, final Class newArrayComponentType) {
if (array != null) {
final int arrayLength = Array.getLength(array);
final Object newArray = Array.newInstance(array.getClass().getComponentType(), arrayLength + 1);
System.arraycopy(array, 0, newArray, 0, arrayLength);
return newArray;
}
return Array.newInstance(newArrayComponentType, 1);
}
}