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RocksDB fat jar to use with Apache Flink
that contains .so files for linux32 and linux64, jnilib files for Mac OSX, and a .dll for Windows x64.
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
package org.rocksdb;
/**
* Options that control write operations.
*
* Note that developers should call WriteOptions.dispose() to release the
* c++ side memory before a WriteOptions instance runs out of scope.
*/
public class WriteOptions extends RocksObject {
/**
* Construct WriteOptions instance.
*/
public WriteOptions() {
super(newWriteOptions());
}
/**
* If true, the write will be flushed from the operating system
* buffer cache (by calling WritableFile::Sync()) before the write
* is considered complete. If this flag is true, writes will be
* slower.
*
* If this flag is false, and the machine crashes, some recent
* writes may be lost. Note that if it is just the process that
* crashes (i.e., the machine does not reboot), no writes will be
* lost even if sync==false.
*
* In other words, a DB write with sync==false has similar
* crash semantics as the "write()" system call. A DB write
* with sync==true has similar crash semantics to a "write()"
* system call followed by "fdatasync()".
*
* Default: false
*
* @param flag a boolean flag to indicate whether a write
* should be synchronized.
* @return the instance of the current WriteOptions.
*/
public WriteOptions setSync(final boolean flag) {
setSync(nativeHandle_, flag);
return this;
}
/**
* If true, the write will be flushed from the operating system
* buffer cache (by calling WritableFile::Sync()) before the write
* is considered complete. If this flag is true, writes will be
* slower.
*
* If this flag is false, and the machine crashes, some recent
* writes may be lost. Note that if it is just the process that
* crashes (i.e., the machine does not reboot), no writes will be
* lost even if sync==false.
*
* In other words, a DB write with sync==false has similar
* crash semantics as the "write()" system call. A DB write
* with sync==true has similar crash semantics to a "write()"
* system call followed by "fdatasync()".
*
* @return boolean value indicating if sync is active.
*/
public boolean sync() {
return sync(nativeHandle_);
}
/**
* If true, writes will not first go to the write ahead log,
* and the write may got lost after a crash.
*
* @param flag a boolean flag to specify whether to disable
* write-ahead-log on writes.
* @return the instance of the current WriteOptions.
*/
public WriteOptions setDisableWAL(final boolean flag) {
setDisableWAL(nativeHandle_, flag);
return this;
}
/**
* If true, writes will not first go to the write ahead log,
* and the write may got lost after a crash.
*
* @return boolean value indicating if WAL is disabled.
*/
public boolean disableWAL() {
return disableWAL(nativeHandle_);
}
private native static long newWriteOptions();
private native void setSync(long handle, boolean flag);
private native boolean sync(long handle);
private native void setDisableWAL(long handle, boolean flag);
private native boolean disableWAL(long handle);
@Override protected final native void disposeInternal(final long handle);
}