ceph/src/rocksdb/java/src/main/java/org/rocksdb/AbstractCompactionFilterFactory.java

   1 // Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5
   6 package org.rocksdb;
   7
   8 /**
   9  * Each compaction will create a new {@link AbstractCompactionFilter}
  10  * allowing the application to know about different compactions
  11  *
  12  * @param <T> The concrete type of the compaction filter
  13  */
  14 public abstract class AbstractCompactionFilterFactory<T extends AbstractCompactionFilter<?>>
  15     extends RocksCallbackObject {
  16
  17   public AbstractCompactionFilterFactory() {
  18     super(null);
  19   }
  20
  21   @Override
  22   protected long initializeNative(final long... nativeParameterHandles) {
  23     return createNewCompactionFilterFactory0();
  24   }
  25
  26   /**
  27    * Called from JNI, see compaction_filter_factory_jnicallback.cc
  28    *
  29    * @param fullCompaction {@link AbstractCompactionFilter.Context#fullCompaction}
  30    * @param manualCompaction {@link AbstractCompactionFilter.Context#manualCompaction}
  31    *
  32    * @return native handle of the CompactionFilter
  33    */
  34   private long createCompactionFilter(final boolean fullCompaction,
  35       final boolean manualCompaction) {
  36     final T filter = createCompactionFilter(
  37         new AbstractCompactionFilter.Context(fullCompaction, manualCompaction));
  38
  39     // CompactionFilterFactory::CreateCompactionFilter returns a std::unique_ptr
  40     // which therefore has ownership of the underlying native object
  41     filter.disOwnNativeHandle();
  42
  43     return filter.nativeHandle_;
  44   }
  45
  46   /**
  47    * Create a new compaction filter
  48    *
  49    * @param context The context describing the need for a new compaction filter
  50    *
  51    * @return A new instance of {@link AbstractCompactionFilter}
  52    */
  53   public abstract T createCompactionFilter(
  54       final AbstractCompactionFilter.Context context);
  55
  56   /**
  57    * A name which identifies this compaction filter
  58    *
  59    * The name will be printed to the LOG file on start up for diagnosis
  60    */
  61   public abstract String name();
  62
  63   /**
  64    * We override {@link RocksCallbackObject#disposeInternal()}
  65    * as disposing of a rocksdb::AbstractCompactionFilterFactory requires
  66    * a slightly different approach as it is a std::shared_ptr
  67    */
  68   @Override
  69   protected void disposeInternal() {
  70     disposeInternal(nativeHandle_);
  71   }
  72
  73   private native long createNewCompactionFilterFactory0();
  74   private native void disposeInternal(final long handle);
  75 }