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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.collections.iterators;
import java.lang.reflect.Array;
import java.util.NoSuchElementException;
import org.apache.commons.collections.ResettableIterator;
/**
* Implements an {@link java.util.Iterator Iterator} over any array.
*
* The array can be either an array of object or of primitives. If you know
* that you have an object array, the
* {@link org.apache.commons.collections.iterators.ObjectArrayIterator ObjectArrayIterator}
* class is a better choice, as it will perform better.
*
* The iterator implements a {@link #reset} method, allowing the reset of
* the iterator back to the start if required.
*
* @since Commons Collections 1.0
* @version $Revision$ $Date$
*
* @author James Strachan
* @author Mauricio S. Moura
* @author Michael A. Smith
* @author Neil O'Toole
* @author Stephen Colebourne
*
* @deprecated Apache Commons Collections version 3.x is being deprecated from AEMaaCS. The upgraded version 4.4 of Commons Collections is already included as replacement. Customers are advised to upgrade to this version of the library. Please note: the package name was changed to org.apache.commons.collections4. Further note that there are AEM APIs currently exposing the old collections classes; these will be updated in upcoming releases.
*/
@Deprecated(since = "2021-04-30")
public class ArrayIterator implements ResettableIterator {
/**
* The array to iterate over
*/
protected Object array;
/**
* The start index to loop from
*/
protected int startIndex = 0;
/**
* The end index to loop to
*/
protected int endIndex = 0;
/**
* The current iterator index
*/
protected int index = 0;
// Constructors
// ----------------------------------------------------------------------
/**
* Constructor for use with setArray.
*
* Using this constructor, the iterator is equivalent to an empty iterator
* until {@link #setArray(Object)} is called to establish the array to iterate over.
*/
public ArrayIterator() {
super();
}
/**
* Constructs an ArrayIterator that will iterate over the values in the
* specified array.
*
* @param array the array to iterate over.
* @throws IllegalArgumentException if array is not an array.
* @throws NullPointerException if array is null
*/
public ArrayIterator(final Object array) {
super();
setArray(array);
}
/**
* Constructs an ArrayIterator that will iterate over the values in the
* specified array from a specific start index.
*
* @param array the array to iterate over.
* @param startIndex the index to start iterating at.
* @throws IllegalArgumentException if array is not an array.
* @throws NullPointerException if array is null
* @throws IndexOutOfBoundsException if the index is invalid
*/
public ArrayIterator(final Object array, final int startIndex) {
super();
setArray(array);
checkBound(startIndex, "start");
this.startIndex = startIndex;
this.index = startIndex;
}
/**
* Construct an ArrayIterator that will iterate over a range of values
* in the specified array.
*
* @param array the array to iterate over.
* @param startIndex the index to start iterating at.
* @param endIndex the index to finish iterating at.
* @throws IllegalArgumentException if array is not an array.
* @throws NullPointerException if array is null
* @throws IndexOutOfBoundsException if either index is invalid
*/
public ArrayIterator(final Object array, final int startIndex, final int endIndex) {
super();
setArray(array);
checkBound(startIndex, "start");
checkBound(endIndex, "end");
if (endIndex < startIndex) {
throw new IllegalArgumentException("End index must not be less than start index.");
}
this.startIndex = startIndex;
this.endIndex = endIndex;
this.index = startIndex;
}
/**
* Checks whether the index is valid or not.
*
* @param bound the index to check
* @param type the index type (for error messages)
* @throws IndexOutOfBoundsException if the index is invalid
*/
protected void checkBound(final int bound, final String type) {
if (bound > this.endIndex) {
throw new ArrayIndexOutOfBoundsException("Attempt to make an ArrayIterator that " + type + "s beyond the end of the array. ");
}
if (bound < 0) {
throw new ArrayIndexOutOfBoundsException("Attempt to make an ArrayIterator that " + type + "s before the start of the array. ");
}
}
// Iterator interface
// -----------------------------------------------------------------------
/**
* Returns true if there are more elements to return from the array.
*
* @return true if there is a next element to return
*/
public boolean hasNext() {
return (index < endIndex);
}
/**
* Returns the next element in the array.
*
* @return the next element in the array
* @throws NoSuchElementException if all the elements in the array
* have already been returned
*/
public Object next() {
if (hasNext() == false) {
throw new NoSuchElementException();
}
return Array.get(array, index++);
}
/**
* Throws {@link UnsupportedOperationException}.
*
* @throws UnsupportedOperationException always
*/
public void remove() {
throw new UnsupportedOperationException("remove() method is not supported");
}
// Properties
// -----------------------------------------------------------------------
/**
* Gets the array that this iterator is iterating over.
*
* @return the array this iterator iterates over, or null if
* the no-arg constructor was used and {@link #setArray(Object)} has never
* been called with a valid array.
*/
public Object getArray() {
return array;
}
/**
* Sets the array that the ArrayIterator should iterate over.
*
* If an array has previously been set (using the single-arg constructor
* or this method) then that array is discarded in favour of this one.
* Iteration is restarted at the start of the new array.
* Although this can be used to reset iteration, the {@link #reset()} method
* is a more effective choice.
*
* @param array the array that the iterator should iterate over.
* @throws IllegalArgumentException if array is not an array.
* @throws NullPointerException if array is null
*/
public void setArray(final Object array) {
// Array.getLength throws IllegalArgumentException if the object is not
// an array or NullPointerException if the object is null. This call
// is made before saving the array and resetting the index so that the
// array iterator remains in a consistent state if the argument is not
// an array or is null.
this.endIndex = Array.getLength(array);
this.startIndex = 0;
this.array = array;
this.index = 0;
}
/**
* Resets the iterator back to the start index.
*/
public void reset() {
this.index = this.startIndex;
}
}