1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.collections4.iterators;
18
19 import java.util.Iterator;
20
21 import org.apache.commons.collections4.functors.UniquePredicate;
22
23 /**
24 * A FilterIterator which only returns "unique" Objects. Internally,
25 * the Iterator maintains a Set of objects it has already encountered,
26 * and duplicate Objects are skipped.
27 *
28 * @param <E> the type of elements returned by this iterator.
29 * @since 2.1
30 */
31 public class UniqueFilterIterator<E> extends FilterIterator<E> {
32
33 /**
34 * Constructs a new {@code UniqueFilterIterator}.
35 *
36 * @param iterator the iterator to use
37 */
38 public UniqueFilterIterator(final Iterator<? extends E> iterator) {
39 super(iterator, UniquePredicate.uniquePredicate());
40 }
41
42 }