| /*- |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.sling.query.iterator; |
| |
| import java.util.Iterator; |
| |
| import org.apache.sling.query.api.internal.Option; |
| import org.apache.sling.query.api.internal.TreeProvider; |
| |
| public class UniqueIterator<T> extends AbstractIterator<Option<T>> { |
| |
| private final Iterator<Option<T>> iterator; |
| |
| private final TreeProvider<T> treeProvider; |
| |
| private T lastElement; |
| |
| public UniqueIterator(Iterator<Option<T>> input, TreeProvider<T> treeProvider) { |
| this.iterator = input; |
| this.treeProvider = treeProvider; |
| } |
| |
| @Override |
| protected Option<T> getElement() { |
| if (!iterator.hasNext()) { |
| return null; |
| } |
| Option<T> candidate = iterator.next(); |
| Option<T> result; |
| if (treeProvider.sameElement(lastElement, candidate.getElement())) { |
| result = Option.empty(candidate.getArgumentId()); |
| } else { |
| result = candidate; |
| } |
| lastElement = candidate.getElement(); |
| return result; |
| } |
| |
| } |