public OutputStream createCompressionStream(OutputStream downStream, Compressor compressor,
      int downStreamBufferSize) throws IOException {
      OutputStream bos1 = null;
      if (downStreamBufferSize > 0) {
        bos1 = new BufferedOutputStream(downStream, downStreamBufferSize);
      } else {
        bos1 = downStream;
      }
      CompressionOutputStream cos = createPlainCompressionStream(bos1, compressor);
      BufferedOutputStream bos2 =
        new BufferedOutputStream(new FinishOnFlushCompressionStream(cos), DATA_OBUF_SIZE);
      return bos2;
    }
Reload configuration for the given algorithm.
<p>
NOTE: Experts only. This can only be done safely during process startup, before the
algorithm's codecs are in use. If the codec implementation is changed, the new implementation
may not be fully compatible with what was loaded at static initialization time, leading to
potential data corruption. Mostly used by unit tests.
@param conf configuration
hbase-common/src/main/java/org/apache/hadoop/hbase/io/compress/Compression.java