Compressed File Extraction in HDFS

Question

I have a .gz file uploaded in the HDFS and I am trying to extract the contents of that file and put it into same directory of HDFS. This is the code I tried:

final String uri = "hdfs://localhost:8020/user/input1/output.gz";
    Path pt=new Path(uri);
    FileSystem fs = FileSystem.get(new Configuration());

    Configuration conf = new Configuration();
    CompressionCodecFactory factory = new CompressionCodecFactory(conf);
    CompressionCodec codec = factory.getCodec(pt);

    if(codec == null){
        System.err.println("No Codec found !!!");
        System.exit(1);
    }

    String outputUri = CompressionCodecFactory.removeSuffix(uri, codec.getDefaultExtension());
    InputStream in = null;
    OutputStream out = null;
    try {
        in = codec.createInputStream(fs.open(pt));
        out = fs.create(new Path(outputUri));
    } finally{
        IOUtils.closeStream(in);
        IOUtils.closeStream(out);
    }

The file is getting extracted but the content is of 0 B. Please advice where is the problem caused.

Answer 1

You forgot to copy data from in to out.

IOUtils.copyBytes(...)