org.rocksdb.CompressionOptions Maven / Gradle / Ivy
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
package org.rocksdb;
/**
* Options for Compression
*/
public class CompressionOptions extends RocksObject {
public CompressionOptions() {
super(newCompressionOptions());
}
public CompressionOptions setWindowBits(final int windowBits) {
setWindowBits(nativeHandle_, windowBits);
return this;
}
public int windowBits() {
return windowBits(nativeHandle_);
}
public CompressionOptions setLevel(final int level) {
setLevel(nativeHandle_, level);
return this;
}
public int level() {
return level(nativeHandle_);
}
public CompressionOptions setStrategy(final int strategy) {
setStrategy(nativeHandle_, strategy);
return this;
}
public int strategy() {
return strategy(nativeHandle_);
}
/**
* Maximum size of dictionary used to prime the compression library. Currently
* this dictionary will be constructed by sampling the first output file in a
* subcompaction when the target level is bottommost. This dictionary will be
* loaded into the compression library before compressing/uncompressing each
* data block of subsequent files in the subcompaction. Effectively, this
* improves compression ratios when there are repetitions across data blocks.
*
* A value of 0 indicates the feature is disabled.
*
* Default: 0.
*
* @param maxDictBytes Maximum bytes to use for the dictionary
*
* @return the reference to the current options
*/
public CompressionOptions setMaxDictBytes(final int maxDictBytes) {
setMaxDictBytes(nativeHandle_, maxDictBytes);
return this;
}
/**
* Maximum size of dictionary used to prime the compression library.
*
* @return The maximum bytes to use for the dictionary
*/
public int maxDictBytes() {
return maxDictBytes(nativeHandle_);
}
/**
* Maximum size of training data passed to zstd's dictionary trainer. Using
* zstd's dictionary trainer can achieve even better compression ratio
* improvements than using {@link #setMaxDictBytes(int)} alone.
*
* The training data will be used to generate a dictionary
* of {@link #maxDictBytes()}.
*
* Default: 0.
*
* @param zstdMaxTrainBytes Maximum bytes to use for training ZStd.
*
* @return the reference to the current options
*/
public CompressionOptions setZStdMaxTrainBytes(final int zstdMaxTrainBytes) {
setZstdMaxTrainBytes(nativeHandle_, zstdMaxTrainBytes);
return this;
}
/**
* Maximum size of training data passed to zstd's dictionary trainer.
*
* @return Maximum bytes to use for training ZStd
*/
public int zstdMaxTrainBytes() {
return zstdMaxTrainBytes(nativeHandle_);
}
/**
* When the compression options are set by the user, it will be set to "true".
* For bottommost_compression_opts, to enable it, user must set enabled=true.
* Otherwise, bottommost compression will use compression_opts as default
* compression options.
*
* For compression_opts, if compression_opts.enabled=false, it is still
* used as compression options for compression process.
*
* Default: false.
*
* @param enabled true to use these compression options
* for the bottommost_compression_opts, false otherwise
*
* @return the reference to the current options
*/
public CompressionOptions setEnabled(final boolean enabled) {
setEnabled(nativeHandle_, enabled);
return this;
}
/**
* Determine whether these compression options
* are used for the bottommost_compression_opts.
*
* @return true if these compression options are used
* for the bottommost_compression_opts, false otherwise
*/
public boolean enabled() {
return enabled(nativeHandle_);
}
private native static long newCompressionOptions();
@Override protected final native void disposeInternal(final long handle);
private native void setWindowBits(final long handle, final int windowBits);
private native int windowBits(final long handle);
private native void setLevel(final long handle, final int level);
private native int level(final long handle);
private native void setStrategy(final long handle, final int strategy);
private native int strategy(final long handle);
private native void setMaxDictBytes(final long handle, final int maxDictBytes);
private native int maxDictBytes(final long handle);
private native void setZstdMaxTrainBytes(final long handle,
final int zstdMaxTrainBytes);
private native int zstdMaxTrainBytes(final long handle);
private native void setEnabled(final long handle, final boolean enabled);
private native boolean enabled(final long handle);
}