解压缩Hadoop hdfs目录中的所有Gzip文件

您需要一个CompressionCodec解压缩文件.gzip的实现是GzipCodec.您可以CompressedInputStream通过编解码器获得一个简单的IO结果.这样的事情:说你有一个文件file.gz

//path of file
String uri = "/uri/to/file.gz";
Configuration conf = new Configuration();
FileSystem fs = FileSystem.get(URI.create(uri), conf);
Path inputPath = new Path(uri);

CompressionCodecFactory factory = new CompressionCodecFactory(conf);
// the correct codec will be discovered by the extension of the file
CompressionCodec codec = factory.getCodec(inputPath);

if (codec == null) {
    System.err.println("No codec found for " + uri);
    System.exit(1);
}

// remove the .gz extension
String outputUri =
    CompressionCodecFactory.removeSuffix(uri, codec.getDefaultExtension());

InputStream is = codec.createInputStream(fs.open(inputPath));
OutputStream out = fs.create(new Path(outputUri));
IOUtils.copyBytes(is, out, conf);

// close streams

UPDATE

如果你需要获取目录中的所有文件,你应该得到FileStatus类似的东西

FileSystem fs = FileSystem.get(new Configuration());
FileStatus[] statuses = fs.listStatus(new Path("hdfs/path/to/dir"));

然后循环

for (FileStatus status: statuses) {
    CompressionCodec codec = factory.getCodec(status.getPath());
    ...
    InputStream is = codec.createInputStream(fs.open(status.getPath());
    ...
}