001/*
002 * ModeShape (http://www.modeshape.org)
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *       http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.modeshape.common.collection;
017
018import java.util.Iterator;
019import java.util.NoSuchElementException;
020import org.modeshape.common.annotation.Immutable;
021
022/**
023 * A reusuable {@link Iterator} implementation that has no elements. Note that the objects are immutable, and therefore may be
024 * shared and reused.
025 * 
026 * @param <T> the type of the elements over which the iteration is being performed
027 */
028@Immutable
029public final class EmptyIterator<T> implements Iterator<T> {
030
031    @Override
032    public boolean hasNext() {
033        return false;
034    }
035
036    @Override
037    public T next() {
038        throw new NoSuchElementException();
039    }
040
041    @Override
042    public void remove() {
043        throw new UnsupportedOperationException();
044    }
045}