chaohParse.huangWordCount.java Source code

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Here is the source code for chaohParse.huangWordCount.java

Source

package chaohParse;

/**
 *  Licensed under the Apace 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.
 */

import java.io.IOException;
import java.util.StringTokenizer;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
//import org.apache.hadoop.fs.shell.Count;
import org.apache.hadoop.io.BytesWritable;
//import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
//import org.apache.hadoop.io.WritableComparator;
//import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;
//import org.junit.internal.matchers.Each;

public class huangWordCount {
    public static class WordMapper extends Mapper<Text, BytesWritable, Text, Text> {
        //private final static IntWritable one = new IntWritable(1);
        //private Text word = new Text();   

        public void map(Text key, BytesWritable value, Context context) throws IOException, InterruptedException {
            System.out.println("begin mapper");
            String tmp = new String(value.getBytes(), "UTF-8");
            String text = parsexml.getContentlineFromXML(tmp);
            text = text.replaceAll("[^A-Za-z \n]", "").toLowerCase();

            StringTokenizer tokenizer = new StringTokenizer(text);

            String tmpString = new String();
            Integer count = new Integer(0);
            while (tokenizer.hasMoreTokens()) {
                tmpString = key.toString() + "-" + tokenizer.nextToken();
                context.write(new Text(tmpString), new Text(count.toString()));
                count += tmpString.length() + 1;
            }
        }
    }

    public static class WordCombiner extends Reducer<Text, Text, Text, Text> {
        private Text outputkeyText = new Text();

        public void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            //System.out.println("begin combine");

            String sum = new String();
            String[] tmpString = key.toString().split("-");
            for (Text val : values) {
                sum += val.toString() + ",";
            }
            outputkeyText = new Text(tmpString[1]);
            //System.out.println(outputkeyText + "---" + tmpString[0]+":"+sum);
            context.write(outputkeyText, new Text(tmpString[0] + ":" + sum));
        }
    }

    public static class WordReducer extends Reducer<Text, Text, Text, Text> {
        public void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            //System.out.println("begin reduce");

            String sum = new String();
            System.out.println("reduce input key:" + key + values.toString());
            for (Text val : values) {
                sum += "[" + val.toString() + "]";
            }
            //System.out.println(key.toString()+"---"+sum);
            context.write(key, new Text(sum));

        }
    }

    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();
        String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
        if (otherArgs.length != 2) {
            System.err.println("Usage: wordcount <in> <out>");
            System.exit(2);
        }
        Job job = new Job(conf, "word count");

        job.setJarByClass(huangWordCount.class);

        job.setMapperClass(WordMapper.class);
        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(Text.class);

        job.setCombinerClass(WordCombiner.class);
        job.setReducerClass(WordReducer.class);

        job.setInputFormatClass(ZipFileInputFormat.class);

        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(Text.class);
        FileInputFormat.addInputPath(job, new Path(otherArgs[0]));
        FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));
        System.exit(job.waitForCompletion(true) ? 0 : 1);
    }
}