@Override
  public String getDefaultExtension() {
    return ".lz4";
  }
Hadoop Lz4 codec implemented with lz4-java.
<p>
This is data format compatible with Hadoop's native lz4 codec.
hbase-compression/hbase-compression-lz4/src/main/java/org/apache/hadoop/hbase/io/compress/lz4/Lz4Codec.java