1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.giraph.edge; 20 21 import org.apache.hadoop.io.Writable; 22 import org.apache.hadoop.io.WritableComparable; 23 24 import java.util.Map; 25 26 /** 27 * Helper class for a mutable edge that modifies the backing map entry. 28 * 29 * @param <I> Vertex id 30 * @param <E> Edge value 31 */ 32 public class MapMutableEdge<I extends WritableComparable, E extends Writable> 33 implements MutableEdge<I, E> { 34 /** Backing entry for the edge in the map. */ 35 private Map.Entry<I, E> entry; 36 37 /** 38 * Set the backing entry for this edge in the map. 39 * 40 * @param entry Backing entry 41 */ 42 public void setEntry(Map.Entry<I, E> entry) { 43 this.entry = entry; 44 } 45 46 @Override 47 public void setValue(E value) { 48 // Replace the value in the map. 49 entry.setValue(value); 50 } 51 52 @Override 53 public I getTargetVertexId() { 54 return entry.getKey(); 55 } 56 57 @Override 58 public E getValue() { 59 return entry.getValue(); 60 } 61 }