/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.giraph.io.formats;
import com.google.common.collect.Lists;
import net.iharder.Base64;
import org.apache.giraph.edge.Edge;
import org.apache.giraph.edge.EdgeFactory;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.ByteArrayInputStream;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.List;
/**
* Simple way to represent the structure of the graph with a JSON object.
* The actual vertex ids, values, edges are stored by the
* Writable serialized bytes that are Byte64 encoded.
* Works with {@link JsonBase64VertexOutputFormat}
*
* @param <I> Vertex index value
* @param <V> Vertex value
* @param <E> Edge value
*/
@SuppressWarnings("rawtypes")
public class JsonBase64VertexInputFormat<I extends WritableComparable,
V extends Writable, E extends Writable>
extends TextVertexInputFormat<I, V, E> {
@Override
public TextVertexReader createVertexReader(InputSplit split,
TaskAttemptContext context) {
return new JsonBase64VertexReader();
}
/**
* Simple reader that supports {@link JsonBase64VertexInputFormat}
*/
protected class JsonBase64VertexReader extends
TextVertexReaderFromEachLineProcessed<JSONObject> {
@Override
public void initialize(InputSplit inputSplit, TaskAttemptContext context)
throws IOException, InterruptedException {
super.initialize(inputSplit, context);
}
@Override
protected JSONObject preprocessLine(Text line) {
try {
return new JSONObject(line.toString());
} catch (JSONException e) {
throw new IllegalArgumentException(
"next: Failed to get the vertex", e);
}
}
@Override
protected I getId(JSONObject vertexObject) throws IOException {
try {
byte[] decodedWritable = Base64.decode(
vertexObject.getString(JsonBase64VertexFormat.VERTEX_ID_KEY));
DataInput input = new DataInputStream(
new ByteArrayInputStream(decodedWritable));
I vertexId = getConf().createVertexId();
vertexId.readFields(input);
return vertexId;
} catch (JSONException e) {
throw new IllegalArgumentException(
"next: Failed to get vertex id", e);
}
}
@Override
protected V getValue(JSONObject vertexObject) throws IOException {
try {
byte[] decodedWritable = Base64.decode(
vertexObject.getString(JsonBase64VertexFormat.VERTEX_VALUE_KEY));
DataInputStream input = new DataInputStream(
new ByteArrayInputStream(decodedWritable));
V vertexValue = getConf().createVertexValue();
vertexValue.readFields(input);
return vertexValue;
} catch (JSONException e) {
throw new IllegalArgumentException(
"next: Failed to get vertex value", e);
}
}
@Override
protected Iterable<Edge<I, E>> getEdges(JSONObject vertexObject) throws
IOException {
JSONArray edgeArray = null;
try {
edgeArray = vertexObject.getJSONArray(
JsonBase64VertexFormat.EDGE_ARRAY_KEY);
} catch (JSONException e) {
throw new IllegalArgumentException(
"next: Failed to get edge array", e);
}
byte[] decodedWritable;
List<Edge<I, E>> edges = Lists.newArrayListWithCapacity(
edgeArray.length());
for (int i = 0; i < edgeArray.length(); ++i) {
try {
decodedWritable = Base64.decode(edgeArray.getString(i));
} catch (JSONException e) {
throw new IllegalArgumentException(
"next: Failed to get edge value", e);
}
DataInputStream input = new DataInputStream(
new ByteArrayInputStream(decodedWritable));
I targetVertexId = getConf().createVertexId();
targetVertexId.readFields(input);
E edgeValue = getConf().createEdgeValue();
edgeValue.readFields(input);
edges.add(EdgeFactory.create(targetVertexId, edgeValue));
}
return edges;
}
}
}