| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. 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.jackrabbit.iterator; |
| |
| import java.util.NoSuchElementException; |
| |
| import javax.jcr.RangeIterator; |
| |
| /** |
| * Array implementation of the JCR |
| * {@link javax.jcr.RangeIterator RangeIterator} interface. This class |
| * implements the RangeIterator functionality for an underlying array |
| * of objects. Used as the base class for the type-specific iterator |
| * classes defined in this package. |
| */ |
| class ArrayIterator implements RangeIterator { |
| |
| /** The current iterator position. */ |
| private int position; |
| |
| /** The underlying array of objects. */ |
| private final Object[] array; |
| |
| /** |
| * Creates an iterator for the given array of objects. |
| * |
| * @param array the objects to iterate |
| */ |
| protected ArrayIterator(Object[] array) { |
| this.position = 0; |
| this.array = array; |
| } |
| |
| /** |
| * Checks whether there are more elements in the array. |
| * |
| * @return <code>true</code> if more elements are available, |
| * <code>false</code> otherwise |
| * @see Iterator#hasNext() |
| */ |
| public boolean hasNext() { |
| return (position < array.length); |
| } |
| |
| /** |
| * Returns the next array element and advances the array position. |
| * |
| * @return next element |
| * @see Iterator#next() |
| */ |
| public Object next() { |
| return array[position++]; |
| } |
| |
| /** |
| * Element removal is not supported. |
| * |
| * @throws UnsupportedOperationException always thrown |
| * @see Iterator#remove() |
| */ |
| public void remove() throws UnsupportedOperationException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * Advances the array position the given number of elements. |
| * |
| * @param items number of items to skip |
| * @throws IllegalArgumentException if the given number of items is negative |
| * @throws NoSuchElementException if skipping past the end of the array |
| * @see RangeIterator#skip(long) |
| */ |
| public void skip(long items) |
| throws IllegalArgumentException, NoSuchElementException { |
| if (items < 0) { |
| throw new IllegalArgumentException("Negative number of items"); |
| } else if (position + items < array.length) { |
| position += items; |
| } else { |
| throw new NoSuchElementException("No more elements in the array"); |
| } |
| } |
| |
| /** |
| * Returns the length of the array. |
| * |
| * @return array length |
| * @see RangeIterator#getSize() |
| */ |
| public long getSize() { |
| return array.length; |
| } |
| |
| /** |
| * Returns the current array position |
| * |
| * @return array position |
| * @see RangeIterator#getPosition() |
| */ |
| public long getPosition() { |
| return position; |
| } |
| |
| } |