/**
* 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.mahout.classifier.email;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.mahout.math.VectorWritable;
import org.apache.mahout.utils.email.MailProcessor;
import java.io.IOException;
import java.util.Locale;
import java.util.regex.Pattern;
/**
* Convert the labels created by the {@link MailProcessor} to one consumable by the classifiers
*/
public class PrepEmailMapper extends Mapper<WritableComparable<?>, VectorWritable, Text, VectorWritable> {
private static final Pattern DASH_DOT = Pattern.compile("-|\\.");
private static final Pattern SLASH = Pattern.compile("\\/");
private boolean useListName = false;//if true, use the project name and the list name in label creation
@Override
protected void setup(Context context) throws IOException, InterruptedException {
useListName = Boolean.parseBoolean(context.getConfiguration().get(PrepEmailVectorsDriver.USE_LIST_NAME));
}
@Override
protected void map(WritableComparable<?> key, VectorWritable value, Context context)
throws IOException, InterruptedException {
String input = key.toString();
///Example: /cocoon.apache.org/dev/200307.gz/001401c3414f$8394e160$1e01a8c0@WRPO
String[] splits = SLASH.split(input);
//we need the first two splits;
if (splits.length >= 3) {
StringBuilder bldr = new StringBuilder();
bldr.append(escape(splits[1]));
if (useListName) {
bldr.append('_').append(escape(splits[2]));
}
context.write(new Text(bldr.toString()), value);
}
}
private static String escape(CharSequence value) {
return DASH_DOT.matcher(value).replaceAll("_").toLowerCase(Locale.ENGLISH);
}
}