[GitHub] accumulo pull request #140: ACCUMULO-4419: Change how compression delegation...

[phrocker <gi...@git.apache.org>]

Github user phrocker commented on a diff in the pull request:

    https://github.com/apache/accumulo/pull/140#discussion_r77162956
  
    --- Diff: core/src/main/java/org/apache/accumulo/core/file/rfile/bcfile/Compression.java ---
    @@ -497,69 +513,66 @@ public CompressionCodec load(Entry<Algorithm,Integer> key) {
         public abstract boolean isSupported();
     
         public Compressor getCompressor() throws IOException {
    -      CompressionCodec codec = getCodec();
    -      if (codec != null) {
    -        Compressor compressor = CodecPool.getCompressor(codec);
    -        if (compressor != null) {
    -          if (compressor.finished()) {
    -            // Somebody returns the compressor to CodecPool but is still using
    -            // it.
    -            LOG.warn("Compressor obtained from CodecPool already finished()");
    -          } else {
    -            LOG.debug("Got a compressor: " + compressor.hashCode());
    -          }
    -          /**
    -           * Following statement is necessary to get around bugs in 0.18 where a compressor is referenced after returned back to the codec pool.
    -           */
    -          compressor.reset();
    -        }
    -        return compressor;
    -      }
    -      return null;
    +      return compressorFactory.getCompressor(this);
         }
     
         public void returnCompressor(Compressor compressor) {
    -      if (compressor != null) {
    -        LOG.debug("Return a compressor: " + compressor.hashCode());
    -        CodecPool.returnCompressor(compressor);
    -      }
    +      compressorFactory.releaseCompressor(this, compressor);
         }
     
         public Decompressor getDecompressor() throws IOException {
    -      CompressionCodec codec = getCodec();
    -      if (codec != null) {
    -        Decompressor decompressor = CodecPool.getDecompressor(codec);
    -        if (decompressor != null) {
    -          if (decompressor.finished()) {
    -            // Somebody returns the decompressor to CodecPool but is still using
    -            // it.
    -            LOG.warn("Decompressor obtained from CodecPool already finished()");
    -          } else {
    -            LOG.debug("Got a decompressor: " + decompressor.hashCode());
    -          }
    -          /**
    -           * Following statement is necessary to get around bugs in 0.18 where a decompressor is referenced after returned back to the codec pool.
    -           */
    -          decompressor.reset();
    -        }
    -        return decompressor;
    -      }
    -
    -      return null;
    +      return compressorFactory.getDecompressor(this);
         }
     
         public void returnDecompressor(Decompressor decompressor) {
    -      if (decompressor != null) {
    -        LOG.debug("Returned a decompressor: " + decompressor.hashCode());
    -        CodecPool.returnDecompressor(decompressor);
    -      }
    +      compressorFactory.releaseDecompressor(this, decompressor);
         }
     
         public String getName() {
           return compressName;
         }
       }
     
    +  /**
    +   * Default implementation will create new compressors.
    +   */
    +  private static CompressorFactory compressorFactory = new CompressorFactory(null);
    +
    +  /**
    +   * Allow the compressor factory to be set within this Instance.
    +   *
    +   * @param compFactory
    +   *          incoming compressor factory to be used by all Algorithms
    +   */
    +  public static synchronized void setCompressionFactory(final CompressorFactory compFactory) {
    +    Preconditions.checkNotNull(compFactory, "Compressor Factory cannot be null");
    +    if (null != compressorFactory) {
    +      compressorFactory.close();
    +    }
    +
    +    compressorFactory = compFactory;
    --- End diff --
    
    Implementations close compressors if they don't own it. I realize the fragility in making sure the release call closes the compressor/decompressor. The alternative I imagined would return a status from release that shows us whether or not the object was released. in that case Compression would call end manually if the factory does not. 


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