| package org.apache.clerezza.commons.rdf.impl.utils.graphmatching; |
| |
| /* |
| * 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. |
| */ |
| |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * An iterator over all possible mapping beetween the elemnets of two sets of |
| * the same size, each mapping maps each element from set1 to a disctinct one of |
| * set2. |
| * |
| * |
| * |
| * @author reto |
| */ |
| class MappingIterator<T,U> implements Iterator<Map<T, U>> { |
| |
| private List<T> list1; |
| private Iterator<List<U>> permutationList2Iterator; |
| |
| |
| public MappingIterator(Set<T> set1, Set<U> set2) { |
| if (set1.size() != set2.size()) { |
| throw new IllegalArgumentException(); |
| } |
| this.list1 = new ArrayList<T>(set1); |
| permutationList2Iterator = new PermutationIterator<U>( |
| new ArrayList<U>(set2)); |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return permutationList2Iterator.hasNext(); |
| } |
| |
| @Override |
| public Map<T, U> next() { |
| List<U> list2 = permutationList2Iterator.next(); |
| Map<T, U> result = new HashMap<T, U>(list1.size()); |
| for (int i = 0; i < list1.size(); i++) { |
| result.put(list1.get(i), list2.get(i)); |
| } |
| return result; |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException("Not supported."); |
| } |
| |
| |
| |
| } |