001 /*
002 * Copyright (C) 2008 The Guava Authors
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 */
016
017 package com.google.common.collect;
018
019 import com.google.common.annotations.GwtCompatible;
020
021 import java.util.Iterator;
022
023 /**
024 * An iterator that does not support {@link #remove}.
025 *
026 * @author Jared Levy
027 * @since 2.0 (imported from Google Collections Library)
028 */
029 @GwtCompatible
030 public abstract class UnmodifiableIterator<E> implements Iterator<E> {
031 /** Constructor for use by subclasses. */
032 protected UnmodifiableIterator() {}
033
034 /**
035 * Guaranteed to throw an exception and leave the underlying data unmodified.
036 *
037 * @throws UnsupportedOperationException always
038 */
039 @Override
040 public final void remove() {
041 throw new UnsupportedOperationException();
042 }
043 }