com.avira.couchdoop.demo.ImportDriver.java Source code

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Here is the source code for com.avira.couchdoop.demo.ImportDriver.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 com.avira.couchdoop.demo;

import com.avira.couchdoop.imp.CouchbaseViewInputFormat;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * Very simple driver for a Couchdoop import.
 */
public class ImportDriver extends Configured implements Tool {

    public static void main(String args[]) {
        int exitCode;
        try {
            exitCode = ToolRunner.run(new ImportDriver(), args);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

        System.exit(exitCode);
    }

    @Override
    public int run(String[] args) throws Exception {
        if (args.length != 1) {
            System.err.println("Usage: <output_path>");
            return 1;
        }
        String output = args[0];

        Job job = Job.getInstance(getConf());
        job.setJarByClass(this.getClass());

        // User classpath takes precedence in favor of Hadoop classpath.
        // This is because the Couchbase client requires a newer version of
        // org.apache.httpcomponents:httpcore.
        job.setUserClassesTakesPrecedence(true);

        // Input
        job.setInputFormatClass(CouchbaseViewInputFormat.class);

        // Mapper
        job.setMapperClass(ImportMapper.class);

        // Reducer
        job.setNumReduceTasks(0);

        // Output
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(Text.class);
        FileOutputFormat.setOutputPath(job, new Path(output));

        if (!job.waitForCompletion(true)) {
            return 2;
        }

        return 0;
    }
}