/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* Licensed 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 eu.stratosphere.test.iterative.nephele.danglingpagerank;
import eu.stratosphere.api.java.record.io.TextInputFormat;
import eu.stratosphere.configuration.Configuration;
import eu.stratosphere.test.iterative.nephele.ConfigUtils;
import eu.stratosphere.types.DoubleValue;
import eu.stratosphere.types.LongValue;
import eu.stratosphere.types.Record;
import java.util.regex.Pattern;
public class DanglingPageGenerateRankInputFormat extends TextInputFormat {
private static final long serialVersionUID = 1L;
private DoubleValue initialRank;
private static final Pattern SEPARATOR = Pattern.compile("[, \t]");
@Override
public void configure(Configuration parameters) {
long numVertices = ConfigUtils.asLong("pageRank.numVertices", parameters);
initialRank = new DoubleValue(1 / (double) numVertices);
super.configure(parameters);
}
@Override
public Record readRecord(Record target, byte[] bytes, int offset, int numBytes) {
String str = new String(bytes, offset, numBytes);
String[] tokens = SEPARATOR.split(str);
long vertexID = Long.parseLong(tokens[0]);
boolean isDangling = tokens.length > 1 && Integer.parseInt(tokens[1]) == 1;
target.clear();
target.addField(new LongValue(vertexID));
target.addField(initialRank);
target.addField(new BooleanValue(isDangling));
return target;
}
}