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.io;
20
21 import java.io.IOException;
22
23 import org.apache.giraph.conf.DefaultImmutableClassesGiraphConfigurable;
24 import org.apache.giraph.edge.Edge;
25 import org.apache.hadoop.io.Writable;
26 import org.apache.hadoop.io.WritableComparable;
27 import org.apache.hadoop.mapreduce.TaskAttemptContext;
28
29 /**
30 *
31 * @param <I> Vertex id
32 * @param <V> Vertex value
33 * @param <E> Edge value
34 */
35 @SuppressWarnings("rawtypes")
36 public abstract class EdgeWriter<
37 I extends WritableComparable, V extends Writable,
38 E extends Writable> extends
39 DefaultImmutableClassesGiraphConfigurable<I, V, E> {
40
41 /**
42 * Writes the next vertex and associated data
43 *
44 * @param sourceId the vertex ID from which the edge originates
45 * @param sourceValue the vertex value; the vertex is the one from which
46 * the edge originates
47 * @param edge edge to be written
48 * @throws IOException
49 * @throws InterruptedException
50 */
51 public abstract void writeEdge(I sourceId, V sourceValue, Edge<I, E> edge)
52 throws IOException, InterruptedException;
53
54 /**
55 * Use the context to setup writing the edges.
56 * Guaranteed to be called prior to any other function.
57 *
58 * @param context Context used to write the vertices.
59 * @throws IOException
60 * @throws InterruptedException
61 */
62 public abstract void initialize(TaskAttemptContext context)
63 throws IOException, InterruptedException;
64
65 /**
66 * Close this {@link EdgeWriter} to future operations.
67 *
68 * @param context the context of the task
69 * @throws IOException
70 * @throws InterruptedException
71 */
72 public abstract void close(TaskAttemptContext context)
73 throws IOException, InterruptedException;
74 }