rocksdb/java/rocksjni/transaction_notifier_jnical...

43 lines
1.5 KiB
C++

// 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).
//
// This file implements the callback "bridge" between Java and C++ for
// ROCKSDB_NAMESPACE::TransactionNotifier.
#ifndef JAVA_ROCKSJNI_TRANSACTION_NOTIFIER_JNICALLBACK_H_
#define JAVA_ROCKSJNI_TRANSACTION_NOTIFIER_JNICALLBACK_H_
#include <jni.h>
#include "rocksdb/utilities/transaction.h"
#include "rocksjni/jnicallback.h"
namespace ROCKSDB_NAMESPACE {
/**
* This class acts as a bridge between C++
* and Java. The methods in this class will be
* called back from the RocksDB TransactionDB or OptimisticTransactionDB (C++),
* we then callback to the appropriate Java method
* this enables TransactionNotifier to be implemented in Java.
*
* Unlike RocksJava's Comparator JNI Callback, we do not attempt
* to reduce Java object allocations by caching the Snapshot object
* presented to the callback. This could be revisited in future
* if performance is lacking.
*/
class TransactionNotifierJniCallback : public JniCallback,
public TransactionNotifier {
public:
TransactionNotifierJniCallback(JNIEnv* env, jobject jtransaction_notifier);
virtual void SnapshotCreated(const Snapshot* newSnapshot);
private:
jmethodID m_jsnapshot_created_methodID;
};
} // namespace ROCKSDB_NAMESPACE
#endif // JAVA_ROCKSJNI_TRANSACTION_NOTIFIER_JNICALLBACK_H_