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.NotThreadSafe;
021
022/**
023 * An {@link Iterator} that is used to iterate over a single, fixed value.
024 * 
025 * @param <T> the value type
026 */
027@NotThreadSafe
028public class SingleIterator<T> implements Iterator<T> {
029    private T value;
030
031    public SingleIterator( T value ) {
032        this.value = value;
033    }
034
035    @Override
036    public boolean hasNext() {
037        return value != null;
038    }
039
040    @Override
041    public T next() {
042        if (value == null) throw new NoSuchElementException();
043        T next = value;
044        value = null;
045        return next;
046    }
047
048    @Override
049    public void remove() {
050        throw new UnsupportedOperationException();
051    }
052}