1/*2 * Licensed to the Apache Software Foundation (ASF) under one3 * or more contributor license agreements. See the NOTICE file4 * distributed with this work for additional information5 * regarding copyright ownership. The ASF licenses this file6 * to you under the Apache License, Version 2.0 (the7 * "License"); you may not use this file except in compliance8 * with the License. You may obtain a copy of the License at9 *10 * http://www.apache.org/licenses/LICENSE-2.011 *12 * Unless required by applicable law or agreed to in writing, software13 * 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 and16 * limitations under the License.17 */1819package org.apache.giraph.edge;
2021import org.apache.hadoop.io.NullWritable;
22import org.apache.hadoop.io.WritableComparable;
2324/**25 * An edge that has no value.26 *27 * @param <I> Vertex ID28 */29publicclass EdgeNoValue<I extends WritableComparable>
30implements ReusableEdge<I, NullWritable> {
31/** Target vertex id */32private I targetVertexId = null;
3334/** Empty constructor */35EdgeNoValue() { }
3637/**38 * Constructor with target vertex ID. Don't call, use EdgeFactory instead.39 *40 * @param targetVertexId vertex ID41 */42EdgeNoValue(I targetVertexId) {
43this.targetVertexId = targetVertexId;
44 }
4546 @Override
47publicvoid setTargetVertexId(I targetVertexId) {
48this.targetVertexId = targetVertexId;
49 }
5051 @Override
52publicvoid setValue(NullWritable value) {
53// do nothing54 }
5556 @Override
57public I getTargetVertexId() {
58return targetVertexId;
59 }
6061 @Override
62public NullWritable getValue() {
63return NullWritable.get();
64 }
6566 @Override
67public String toString() {
68return"(targetVertexId = " + targetVertexId + ")";
69 }
70 }