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.graph;
20
21 import org.apache.giraph.edge.Edge;
22 import org.apache.hadoop.io.Writable;
23 import org.apache.hadoop.io.WritableComparable;
24
25 import java.util.List;
26
27 /**
28 * Structure to hold all the possible graph mutations that can occur during a
29 * superstep.
30 *
31 * @param <I> Vertex index value
32 * @param <V> Vertex value
33 * @param <E> Edge value
34 */
35 @SuppressWarnings("rawtypes")
36 public interface VertexChanges<I extends WritableComparable,
37 V extends Writable, E extends Writable> {
38 /**
39 * Get the added vertices for this particular vertex index from the previous
40 * superstep.
41 *
42 * @return List of vertices for this vertex index.
43 */
44 List<Vertex<I, V, E>> getAddedVertexList();
45
46 /**
47 * Get the number of times this vertex was removed in the previous
48 * superstep.
49 *
50 * @return Count of time this vertex was removed in the previous superstep
51 */
52 int getRemovedVertexCount();
53
54 /**
55 * Get the added edges for this particular vertex index from the previous
56 * superstep
57 *
58 * @return List of added edges for this vertex index
59 */
60 List<Edge<I, E>> getAddedEdgeList();
61
62 /**
63 * Get the removed edges by their destination vertex index.
64 *
65 * @return List of destination edges for removal from this vertex index
66 */
67 List<I> getRemovedEdgeList();
68 }