EmptyIterator.java

/*
 * ModeShape (http://www.modeshape.org)
 *
 * 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.modeshape.common.collection;

import java.util.Iterator;
import java.util.NoSuchElementException;
import org.modeshape.common.annotation.Immutable;

/**
 * A reusuable {@link Iterator} implementation that has no elements. Note that the objects are immutable, and therefore may be
 * shared and reused.
 * 
 * @param <T> the type of the elements over which the iteration is being performed
 */
@Immutable
public final class EmptyIterator<T> implements Iterator<T> {

    @Override
    public boolean hasNext() {
        return false;
    }

    @Override
    public T next() {
        throw new NoSuchElementException();
    }

    @Override
    public void remove() {
        throw new UnsupportedOperationException();
    }
}