hadoop.examples.hdfs.SequenceFileWriteDemo.java Source code

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Here is the source code for hadoop.examples.hdfs.SequenceFileWriteDemo.java

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/*
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package hadoop.examples.hdfs;

import java.net.URI;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.Text;

/**
 * @author <a href="mailto:haithanh0809@gmail.com">Nguyen Thanh Hai</a>
 * @version $Id$
 *
 */
public class SequenceFileWriteDemo {

    private static String[] DATA = { "One, two hello world", "Three, four, goodbye baby", "Five, six, save money",
            "Seven, eight, write code more and more", "Nine, ten, rest in peace" };

    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();
        String uri = "hdfs://exoplatform:9000/user/haint/temp.file";
        Path path = new Path(uri);
        FileSystem fs = FileSystem.get(URI.create(uri), conf);

        //
        IntWritable key = new IntWritable();
        Text value = new Text();
        SequenceFile.Writer writer = null;
        try {
            writer = SequenceFile.createWriter(fs, conf, path, key.getClass(), value.getClass());
            for (int i = 0; i < 100; i++) {
                key.set(100 - i);
                value.set(DATA[i % DATA.length]);
                System.out.printf("[%s]\t%s\t%s\n", writer.getLength(), key, value);
                writer.append(key, value);
            }
        } finally {
            IOUtils.closeStream(writer);
        }
    }
}