Groovy example source code file (ReverseListIterator.java)

This example Groovy source code file (ReverseListIterator.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

iterator, iterator, listiterator, listiterator, reverselistiterator, reverselistiterator, t, t, util

The Groovy ReverseListIterator.java source code

/*
 * Copyright 2003-2010 the original author or authors.
 *
 * Licensed 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.codehaus.groovy.runtime;

import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;

/**
 * A reverse iterator over a list. Utilizes the {@link ListIterator}
 * obtained from the provided {@link List} and converts it to an
 * {@link Iterator} that efficiently traverses the <code>List in
 * reverse. The fail-fast semantics of this iterator are the same as the
 * semantics of the underlying <code>ListIterator.
 *
 * @author Mike Dillon
 */
public class ReverseListIterator<T> implements Iterator {
    private ListIterator<T> delegate;

    /**
     * Constructs a new <code>ReverseListIterator for the provided list.
     * @param list the list to iterate over in reverse
     */
    public ReverseListIterator(List<T> list) {
        this.delegate = list.listIterator(list.size());
    }

    /**
     * {@inheritDoc}
     */
    public boolean hasNext() {
        return delegate.hasPrevious();
    }

    /**
     * {@inheritDoc}
     */
    public T next() {
        return delegate.previous();
    }

    /**
     * {@inheritDoc}
     */
    public void remove() {
        delegate.remove();
    }
}