rocksdb/java/rocksjni/rocksjni.cc
Yueh-Hsuan Chiang e72b02e3c2 [Java] Add basic Java binding for rocksdb::Env.
Summary: Add basic Java binding for rocksdb::Env.

Test Plan:
make rocksdbjava
make jtest
cd java
./jdb_bench.sh --max_background_compactions=1
./jdb_bench.sh --max_background_compactions=10

Reviewers: sdong, ankgup87, haobo

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18903
2014-06-05 17:09:25 -07:00

437 lines
14 KiB
C++

// Copyright (c) 2014, 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.
//
// This file implements the "bridge" between Java and C++ and enables
// calling c++ rocksdb::DB methods from Java side.
#include <stdio.h>
#include <stdlib.h>
#include <jni.h>
#include <string>
#include <vector>
#include "include/org_rocksdb_RocksDB.h"
#include "rocksjni/portal.h"
#include "rocksdb/db.h"
#include "rocksdb/cache.h"
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::Open
/*
* Class: org_rocksdb_RocksDB
* Method: open
* Signature: (JLjava/lang/String;)V
*/
void Java_org_rocksdb_RocksDB_open(
JNIEnv* env, jobject jdb, jlong jopt_handle,
jlong jcache_size, jstring jdb_path) {
auto opt = reinterpret_cast<rocksdb::Options*>(jopt_handle);
if (jcache_size > 0) {
opt->no_block_cache = false;
opt->block_cache = rocksdb::NewLRUCache(jcache_size);
} else {
opt->no_block_cache = true;
opt->block_cache = nullptr;
}
rocksdb::DB* db = nullptr;
const char* db_path = env->GetStringUTFChars(jdb_path, 0);
rocksdb::Status s = rocksdb::DB::Open(*opt, db_path, &db);
env->ReleaseStringUTFChars(jdb_path, db_path);
if (s.ok()) {
rocksdb::RocksDBJni::setHandle(env, jdb, db);
return;
}
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
}
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::Put
void rocksdb_put_helper(
JNIEnv* env, rocksdb::DB* db, const rocksdb::WriteOptions& write_options,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
jbyte* key = env->GetByteArrayElements(jkey, 0);
jbyte* value = env->GetByteArrayElements(jvalue, 0);
rocksdb::Slice key_slice(reinterpret_cast<char*>(key), jkey_len);
rocksdb::Slice value_slice(reinterpret_cast<char*>(value), jvalue_len);
rocksdb::Status s = db->Put(write_options, key_slice, value_slice);
// trigger java unref on key and value.
// by passing JNI_ABORT, it will simply release the reference without
// copying the result back to the java byte array.
env->ReleaseByteArrayElements(jkey, key, JNI_ABORT);
env->ReleaseByteArrayElements(jvalue, value, JNI_ABORT);
if (s.ok()) {
return;
}
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
}
/*
* Class: org_rocksdb_RocksDB
* Method: put
* Signature: (J[BI[BI)V
*/
void Java_org_rocksdb_RocksDB_put__J_3BI_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
auto db = reinterpret_cast<rocksdb::DB*>(jdb_handle);
static const rocksdb::WriteOptions default_write_options =
rocksdb::WriteOptions();
rocksdb_put_helper(env, db, default_write_options,
jkey, jkey_len,
jvalue, jvalue_len);
}
/*
* Class: org_rocksdb_RocksDB
* Method: put
* Signature: (JJ[BI[BI)V
*/
void Java_org_rocksdb_RocksDB_put__JJ_3BI_3BI(
JNIEnv* env, jobject jdb,
jlong jdb_handle, jlong jwrite_options_handle,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
auto db = reinterpret_cast<rocksdb::DB*>(jdb_handle);
auto write_options = reinterpret_cast<rocksdb::WriteOptions*>(
jwrite_options_handle);
rocksdb_put_helper(env, db, *write_options,
jkey, jkey_len,
jvalue, jvalue_len);
}
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::Write
/*
* Class: org_rocksdb_RocksDB
* Method: write
* Signature: (JJ)V
*/
void Java_org_rocksdb_RocksDB_write(
JNIEnv* env, jobject jdb,
jlong jwrite_options_handle, jlong jbatch_handle) {
rocksdb::DB* db = rocksdb::RocksDBJni::getHandle(env, jdb);
auto write_options = reinterpret_cast<rocksdb::WriteOptions*>(
jwrite_options_handle);
auto batch = reinterpret_cast<rocksdb::WriteBatch*>(jbatch_handle);
rocksdb::Status s = db->Write(*write_options, batch);
if (!s.ok()) {
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
}
}
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::Get
jbyteArray rocksdb_get_helper(
JNIEnv* env, rocksdb::DB* db, const rocksdb::ReadOptions& read_opt,
jbyteArray jkey, jint jkey_len) {
jboolean isCopy;
jbyte* key = env->GetByteArrayElements(jkey, &isCopy);
rocksdb::Slice key_slice(
reinterpret_cast<char*>(key), jkey_len);
std::string value;
rocksdb::Status s = db->Get(
read_opt, key_slice, &value);
// trigger java unref on key.
// by passing JNI_ABORT, it will simply release the reference without
// copying the result back to the java byte array.
env->ReleaseByteArrayElements(jkey, key, JNI_ABORT);
if (s.IsNotFound()) {
return nullptr;
}
if (s.ok()) {
jbyteArray jvalue = env->NewByteArray(value.size());
env->SetByteArrayRegion(
jvalue, 0, value.size(),
reinterpret_cast<const jbyte*>(value.c_str()));
return jvalue;
}
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
return nullptr;
}
/*
* Class: org_rocksdb_RocksDB
* Method: get
* Signature: (J[BI)[B
*/
jbyteArray Java_org_rocksdb_RocksDB_get__J_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jbyteArray jkey, jint jkey_len) {
return rocksdb_get_helper(env,
reinterpret_cast<rocksdb::DB*>(jdb_handle),
rocksdb::ReadOptions(),
jkey, jkey_len);
}
/*
* Class: org_rocksdb_RocksDB
* Method: get
* Signature: (JJ[BI)[B
*/
jbyteArray Java_org_rocksdb_RocksDB_get__JJ_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle, jlong jropt_handle,
jbyteArray jkey, jint jkey_len) {
return rocksdb_get_helper(env,
reinterpret_cast<rocksdb::DB*>(jdb_handle),
*reinterpret_cast<rocksdb::ReadOptions*>(jropt_handle),
jkey, jkey_len);
}
jint rocksdb_get_helper(
JNIEnv* env, rocksdb::DB* db, const rocksdb::ReadOptions& read_options,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
static const int kNotFound = -1;
static const int kStatusError = -2;
jbyte* key = env->GetByteArrayElements(jkey, 0);
rocksdb::Slice key_slice(
reinterpret_cast<char*>(key), jkey_len);
// TODO(yhchiang): we might save one memory allocation here by adding
// a DB::Get() function which takes preallocated jbyte* as input.
std::string cvalue;
rocksdb::Status s = db->Get(
read_options, key_slice, &cvalue);
// trigger java unref on key.
// by passing JNI_ABORT, it will simply release the reference without
// copying the result back to the java byte array.
env->ReleaseByteArrayElements(jkey, key, JNI_ABORT);
if (s.IsNotFound()) {
return kNotFound;
} else if (!s.ok()) {
// Here since we are throwing a Java exception from c++ side.
// As a result, c++ does not know calling this function will in fact
// throwing an exception. As a result, the execution flow will
// not stop here, and codes after this throw will still be
// executed.
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
// Return a dummy const value to avoid compilation error, although
// java side might not have a chance to get the return value :)
return kStatusError;
}
int cvalue_len = static_cast<int>(cvalue.size());
int length = std::min(jvalue_len, cvalue_len);
env->SetByteArrayRegion(
jvalue, 0, length,
reinterpret_cast<const jbyte*>(cvalue.c_str()));
return cvalue_len;
}
jobject multi_get_helper(JNIEnv* env, jobject jdb, rocksdb::DB* db,
const rocksdb::ReadOptions& rOpt, jobject jkey_list, jint jkeys_count) {
std::vector<rocksdb::Slice> keys;
std::vector<jbyte*> keys_to_free;
// get iterator
jobject iteratorObj = env->CallObjectMethod(
jkey_list, rocksdb::ListJni::getIteratorMethod(env));
// iterate over keys and convert java byte array to slice
while(env->CallBooleanMethod(
iteratorObj, rocksdb::ListJni::getHasNextMethod(env)) == JNI_TRUE) {
jbyteArray jkey = (jbyteArray) env->CallObjectMethod(
iteratorObj, rocksdb::ListJni::getNextMethod(env));
jint key_length = env->GetArrayLength(jkey);
jbyte* key = new jbyte[key_length];
env->GetByteArrayRegion(jkey, 0, key_length, key);
// store allocated jbyte to free it after multiGet call
keys_to_free.push_back(key);
rocksdb::Slice key_slice(
reinterpret_cast<char*>(key), key_length);
keys.push_back(key_slice);
}
std::vector<std::string> values;
std::vector<rocksdb::Status> s = db->MultiGet(rOpt, keys, &values);
// Don't reuse class pointer
jclass jclazz = env->FindClass("java/util/ArrayList");
jmethodID mid = rocksdb::ListJni::getArrayListConstructorMethodId(
env, jclazz);
jobject jvalue_list = env->NewObject(jclazz, mid, jkeys_count);
// insert in java list
for(std::vector<rocksdb::Status>::size_type i = 0; i != s.size(); i++) {
if(s[i].ok()) {
jbyteArray jvalue = env->NewByteArray(values[i].size());
env->SetByteArrayRegion(
jvalue, 0, values[i].size(),
reinterpret_cast<const jbyte*>(values[i].c_str()));
env->CallBooleanMethod(
jvalue_list, rocksdb::ListJni::getListAddMethodId(env), jvalue);
}
else {
env->CallBooleanMethod(
jvalue_list, rocksdb::ListJni::getListAddMethodId(env), nullptr);
}
}
// free up allocated byte arrays
for(std::vector<jbyte*>::size_type i = 0; i != keys_to_free.size(); i++) {
delete[] keys_to_free[i];
}
keys_to_free.clear();
return jvalue_list;
}
/*
* Class: org_rocksdb_RocksDB
* Method: multiGet
* Signature: (JLjava/util/List;I)Ljava/util/List;
*/
jobject Java_org_rocksdb_RocksDB_multiGet__JLjava_util_List_2I(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jobject jkey_list, jint jkeys_count) {
return multi_get_helper(env, jdb, reinterpret_cast<rocksdb::DB*>(jdb_handle),
rocksdb::ReadOptions(), jkey_list, jkeys_count);
}
/*
* Class: org_rocksdb_RocksDB
* Method: multiGet
* Signature: (JJLjava/util/List;I)Ljava/util/List;
*/
jobject Java_org_rocksdb_RocksDB_multiGet__JJLjava_util_List_2I(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jlong jropt_handle, jobject jkey_list, jint jkeys_count) {
return multi_get_helper(env, jdb, reinterpret_cast<rocksdb::DB*>(jdb_handle),
*reinterpret_cast<rocksdb::ReadOptions*>(jropt_handle), jkey_list,
jkeys_count);
}
/*
* Class: org_rocksdb_RocksDB
* Method: get
* Signature: (J[BI[BI)I
*/
jint Java_org_rocksdb_RocksDB_get__J_3BI_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
return rocksdb_get_helper(env,
reinterpret_cast<rocksdb::DB*>(jdb_handle),
rocksdb::ReadOptions(),
jkey, jkey_len, jvalue, jvalue_len);
}
/*
* Class: org_rocksdb_RocksDB
* Method: get
* Signature: (JJ[BI[BI)I
*/
jint Java_org_rocksdb_RocksDB_get__JJ_3BI_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle, jlong jropt_handle,
jbyteArray jkey, jint jkey_len,
jbyteArray jvalue, jint jvalue_len) {
return rocksdb_get_helper(env,
reinterpret_cast<rocksdb::DB*>(jdb_handle),
*reinterpret_cast<rocksdb::ReadOptions*>(jropt_handle),
jkey, jkey_len, jvalue, jvalue_len);
}
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::Delete()
void rocksdb_remove_helper(
JNIEnv* env, rocksdb::DB* db, const rocksdb::WriteOptions& write_options,
jbyteArray jkey, jint jkey_len) {
jbyte* key = env->GetByteArrayElements(jkey, 0);
rocksdb::Slice key_slice(reinterpret_cast<char*>(key), jkey_len);
rocksdb::Status s = db->Delete(write_options, key_slice);
// trigger java unref on key and value.
// by passing JNI_ABORT, it will simply release the reference without
// copying the result back to the java byte array.
env->ReleaseByteArrayElements(jkey, key, JNI_ABORT);
if (!s.ok()) {
rocksdb::RocksDBExceptionJni::ThrowNew(env, s);
}
return;
}
/*
* Class: org_rocksdb_RocksDB
* Method: remove
* Signature: (J[BI)V
*/
void Java_org_rocksdb_RocksDB_remove__J_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jbyteArray jkey, jint jkey_len) {
auto db = reinterpret_cast<rocksdb::DB*>(jdb_handle);
static const rocksdb::WriteOptions default_write_options =
rocksdb::WriteOptions();
rocksdb_remove_helper(env, db, default_write_options, jkey, jkey_len);
}
/*
* Class: org_rocksdb_RocksDB
* Method: remove
* Signature: (JJ[BI)V
*/
void Java_org_rocksdb_RocksDB_remove__JJ_3BI(
JNIEnv* env, jobject jdb, jlong jdb_handle,
jlong jwrite_options, jbyteArray jkey, jint jkey_len) {
auto db = reinterpret_cast<rocksdb::DB*>(jdb_handle);
auto write_options = reinterpret_cast<rocksdb::WriteOptions*>(jwrite_options);
rocksdb_remove_helper(env, db, *write_options, jkey, jkey_len);
}
//////////////////////////////////////////////////////////////////////////////
// rocksdb::DB::~DB()
/*
* Class: org_rocksdb_RocksDB
* Method: disposeInternal
* Signature: (J)V
*/
void Java_org_rocksdb_RocksDB_disposeInternal(
JNIEnv* env, jobject java_db, jlong jhandle) {
delete reinterpret_cast<rocksdb::DB*>(jhandle);
}
/*
* Class: org_rocksdb_RocksDB
* Method: iterator0
* Signature: (J)J
*/
jlong Java_org_rocksdb_RocksDB_iterator0(
JNIEnv* env, jobject jdb, jlong db_handle) {
auto db = reinterpret_cast<rocksdb::DB*>(db_handle);
rocksdb::Iterator* iterator = db->NewIterator(rocksdb::ReadOptions());
return reinterpret_cast<jlong>(iterator);
}