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.utils;
20
21 import org.apache.hadoop.io.Writable;
22 import org.apache.hadoop.io.WritableComparable;
23
24 /**
25 * Special iterator that reuses vertex ids and message objects so that the
26 * lifetime of the object is only until next() is called.
27 *
28 * @param <I> vertexId type parameter
29 * @param <M> message type parameter
30 */
31 public class ByteStructVertexIdMessageIterator<I extends WritableComparable,
32 M extends Writable> extends ByteStructVertexIdDataIterator<I, M>
33 implements VertexIdMessageIterator<I, M> {
34
35 /**
36 * Constructor with vertexIdData
37 *
38 * @param vertexIdData vertexIdData
39 */
40 public ByteStructVertexIdMessageIterator(
41 AbstractVertexIdData<I, M> vertexIdData) {
42 super(vertexIdData);
43 }
44
45 @Override
46 public M getCurrentMessage() {
47 return getCurrentData();
48 }
49
50 @Override
51 public int getCurrentMessageSize() {
52 return getCurrentDataSize();
53 }
54
55 @Override
56 public boolean isNewMessage() {
57 return true;
58 }
59 }