| /* |
| * 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.logging.log4j.core.util; |
| |
| import java.util.Iterator; |
| import java.util.NoSuchElementException; |
| |
| /** |
| * An {@link java.util.Iterator Iterator} over an array of objects. |
| * <p> |
| * This iterator does not support {@link #remove}, as the object array cannot be |
| * structurally modified. |
| * <p> |
| * The iterator implements a {@link #reset} method, allowing the reset of the iterator |
| * back to the start if required. |
| * |
| * @param <E> the type to iterate over |
| * @since 3.0 |
| * @version $Id: ObjectArrayIterator.java 1734648 2016-03-11 23:51:22Z ggregory $ |
| */ |
| public class ObjectArrayIterator<E> implements /*Resettable*/ Iterator<E> { |
| |
| /** The array */ |
| final E[] array; |
| /** The start index to loop from */ |
| final int startIndex; |
| /** The end index to loop to */ |
| final int endIndex; |
| /** The current iterator index */ |
| int index = 0; |
| |
| //------------------------------------------------------------------------- |
| /** |
| * Constructs an ObjectArrayIterator that will iterate over the values in the |
| * specified array. |
| * |
| * @param array the array to iterate over |
| * @throws NullPointerException if <code>array</code> is <code>null</code> |
| */ |
| @SafeVarargs |
| public ObjectArrayIterator(final E... array) { |
| this(array, 0, array.length); |
| } |
| |
| /** |
| * Constructs an ObjectArrayIterator that will iterate over the values in the |
| * specified array from a specific start index. |
| * |
| * @param array the array to iterate over |
| * @param start the index to start iterating at |
| * @throws NullPointerException if <code>array</code> is <code>null</code> |
| * @throws IndexOutOfBoundsException if the start index is out of bounds |
| */ |
| public ObjectArrayIterator(final E array[], final int start) { |
| this(array, start, array.length); |
| } |
| |
| /** |
| * Construct an ObjectArrayIterator that will iterate over a range of values |
| * in the specified array. |
| * |
| * @param array the array to iterate over |
| * @param start the index to start iterating at |
| * @param end the index (exclusive) to finish iterating at |
| * @throws IndexOutOfBoundsException if the start or end index is out of bounds |
| * @throws IllegalArgumentException if end index is before the start |
| * @throws NullPointerException if <code>array</code> is <code>null</code> |
| */ |
| public ObjectArrayIterator(final E array[], final int start, final int end) { |
| super(); |
| if (start < 0) { |
| throw new ArrayIndexOutOfBoundsException("Start index must not be less than zero"); |
| } |
| if (end > array.length) { |
| throw new ArrayIndexOutOfBoundsException("End index must not be greater than the array length"); |
| } |
| if (start > array.length) { |
| throw new ArrayIndexOutOfBoundsException("Start index must not be greater than the array length"); |
| } |
| if (end < start) { |
| throw new IllegalArgumentException("End index must not be less than start index"); |
| } |
| this.array = array; |
| this.startIndex = start; |
| this.endIndex = end; |
| this.index = start; |
| } |
| |
| // Iterator interface |
| //------------------------------------------------------------------------- |
| |
| /** |
| * Returns true if there are more elements to return from the array. |
| * |
| * @return true if there is a next element to return |
| */ |
| @Override |
| public boolean hasNext() { |
| return this.index < this.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 |
| */ |
| @Override |
| public E next() { |
| if (hasNext() == false) { |
| throw new NoSuchElementException(); |
| } |
| return this.array[this.index++]; |
| } |
| |
| /** |
| * Throws {@link UnsupportedOperationException}. |
| * |
| * @throws UnsupportedOperationException always |
| */ |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException("remove() method is not supported for an ObjectArrayIterator"); |
| } |
| |
| // Properties |
| //------------------------------------------------------------------------- |
| |
| /** |
| * Gets the array that this iterator is iterating over. |
| * |
| * @return the array this iterator iterates over |
| */ |
| public E[] getArray() { |
| return this.array; |
| } |
| |
| /** |
| * Gets the start index to loop from. |
| * |
| * @return the start index |
| */ |
| public int getStartIndex() { |
| return this.startIndex; |
| } |
| |
| /** |
| * Gets the end index to loop to. |
| * |
| * @return the end index |
| */ |
| public int getEndIndex() { |
| return this.endIndex; |
| } |
| |
| /** |
| * Resets the iterator back to the start index. |
| */ |
| //@Override |
| public void reset() { |
| this.index = this.startIndex; |
| } |
| |
| } |