Reading and Writing Sequencefile using Hadoop 2.0 Apis

Question

I am looking for an example which is using the new API to read and write Sequence Files.

Effectively I need to know how to use these functions

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Answer 1

public class SequenceFilesTest {
  @Test
  public void testSeqFileReadWrite() throws IOException {
    Configuration conf = new Configuration();
    FileSystem fs = FileSystem.getLocal(conf);
    Path seqFilePath = new Path("file.seq");
    SequenceFile.Writer writer = SequenceFile.createWriter(conf,
            Writer.file(seqFilePath), Writer.keyClass(Text.class),
            Writer.valueClass(IntWritable.class));

    writer.append(new Text("key1"), new IntWritable(1));
    writer.append(new Text("key2"), new IntWritable(2));

    writer.close();

    SequenceFile.Reader reader = new SequenceFile.Reader(conf,
            Reader.file(seqFilePath));

    Text key = new Text();
    IntWritable val = new IntWritable();

    while (reader.next(key, val)) {
        System.err.println(key + "\t" + val);
    }

    reader.close();
  }
}