org.cloudata.examples.first.HdfsToCloudataMapReduce.java Source code

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Here is the source code for org.cloudata.examples.first.HdfsToCloudataMapReduce.java

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/**
 * 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.cloudata.examples.first;

import java.io.IOException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.cloudata.core.client.Cell;
import org.cloudata.core.client.CTable;
import org.cloudata.core.client.Row;
import org.cloudata.core.common.conf.CloudataConf;
import org.cloudata.core.parallel.hadoop.AbstractTabletInputFormat;
import org.cloudata.core.parallel.hadoop.CloudataMapReduceUtil;
import org.cloudata.core.tablet.TableSchema;

/**
 * @author jindolk
 *
 */
public class HdfsToCloudataMapReduce {
    public static void main(String[] args) throws IOException {
        (new HdfsToCloudataMapReduce()).run(args);
    }

    public void run(String[] args) throws IOException {
        if (args.length < 2) {
            System.out.println("Usage: java HdfsToCloudataMapReduce <input path> <table name>");
            System.exit(0);
        }

        Path inputPath = new Path(args[0]);
        String tableName = args[1];

        CloudataConf nconf = new CloudataConf();
        if (!CTable.existsTable(nconf, tableName)) {
            TableSchema tableSchema = new TableSchema(tableName);
            tableSchema.addColumn("col1");

            CTable.createTable(nconf, tableSchema);
        }

        JobConf jobConf = new JobConf(HdfsToCloudataMapReduce.class);
        String libDir = CloudataMapReduceUtil.initMapReduce(jobConf);

        // <MAP>
        FileInputFormat.addInputPath(jobConf, inputPath);
        jobConf.setInputFormat(TextInputFormat.class);
        jobConf.setMapperClass(HdfsToCloudataMappper.class);
        jobConf.set(AbstractTabletInputFormat.OUTPUT_TABLE, tableName);
        // </MAP>

        // <REDUCE>
        // Map Only
        FileOutputFormat.setOutputPath(jobConf, new Path("HdfsToCloudataMapReduce_" + System.currentTimeMillis()));
        jobConf.setNumReduceTasks(0);
        // </REDUCE>

        try {
            JobClient.runJob(jobConf);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            FileSystem fs = FileSystem.get(jobConf);
            fs.delete(FileOutputFormat.getOutputPath(jobConf), true);
            CloudataMapReduceUtil.clearMapReduce(libDir);
        }
    }

    static class HdfsToCloudataMappper implements Mapper<LongWritable, Text, Text, Text> {
        static Log LOG = LogFactory.getLog(HdfsToCloudataMappper.class.getName());

        private CTable ctable;

        private IOException err;

        private int count = 0;

        @Override
        public void map(LongWritable key, Text value, OutputCollector<Text, Text> output, Reporter reporter)
                throws IOException {
            if (err != null) {
                throw err;
            }
            String record = value.toString();
            Row.Key rowKey = new Row.Key(record);
            Row row = new Row(rowKey);
            row.addCell("col1", new Cell(Cell.Key.EMPTY_KEY, "TestData".getBytes()));
            ctable.put(row);

            count++;
            if (count % 1000 == 0) {
                LOG.info(count + " inserted");
            }
        }

        @Override
        public void configure(JobConf job) {
            try {
                String tableName = job.get(AbstractTabletInputFormat.OUTPUT_TABLE);
                CloudataConf nconf = new CloudataConf(job);
                ctable = CTable.openTable(nconf, tableName);
                if (ctable == null) {
                    throw new IOException("No table:" + tableName);
                }
            } catch (Exception e) {
                err = new IOException(e.getMessage());
                err.initCause(e);
            }
        }

        @Override
        public void close() throws IOException {
            LOG.info(count + " pages inserted");
        }
    }
}