be/src/rpc/jni-thrift-util.h

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// KIND, either express or implied.  See the License for the
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#ifndef IMPALA_RPC_JNI_THRIFT_UTIL_H
#define IMPALA_RPC_JNI_THRIFT_UTIL_H

#include "rpc/thrift-util.h"
#include "util/jni-util.h"

/// Utility functions that depend on both JNI and Thrift, kept separate to reduce
/// unnecessary dependencies where we just want to use one or the other.

namespace impala {

template <class T>
Status SerializeThriftMsg(JNIEnv* env, T* msg, jbyteArray* serialized_msg) {
  int buffer_size = 100 * 1024;  // start out with 100KB
  ThriftSerializer serializer(false, buffer_size);

  uint8_t* buffer = NULL;
  uint32_t size = 0;
  RETURN_IF_ERROR(serializer.SerializeToBuffer(msg, &size, &buffer));

  /// create jbyteArray given buffer
  *serialized_msg = env->NewByteArray(size);
  RETURN_ERROR_IF_EXC(env);
  if (*serialized_msg == NULL) return Status("couldn't construct jbyteArray");
  env->SetByteArrayRegion(*serialized_msg, 0, size, reinterpret_cast<jbyte*>(buffer));
  RETURN_ERROR_IF_EXC(env);
  return Status::OK();
}

template <class T>
Status DeserializeThriftMsg(JNIEnv* env, jbyteArray serialized_msg, T* deserialized_msg) {
  jboolean is_copy = false;
  uint32_t buf_size = env->GetArrayLength(serialized_msg);
  jbyte* buf = env->GetByteArrayElements(serialized_msg, &is_copy);

  RETURN_IF_ERROR(DeserializeThriftMsg(
          reinterpret_cast<uint8_t*>(buf), &buf_size, false, deserialized_msg));

  /// Return buffer back. JNI_ABORT indicates to not copy contents back to java
  /// side.
  env->ReleaseByteArrayElements(serialized_msg, buf, JNI_ABORT);
  return Status::OK();
}

}

#endif