// 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

// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, either express or implied.  See the License for the

// specific language governing permissions and limitations

// under the License.

#include "util/jni-util.h"

#include <fmt/format.h>

#include <glog/logging.h>

#include <jni.h>

#include <jni_md.h>

#include <algorithm>

#include <cstdlib>

#include <filesystem>

#include <iterator>

#include <limits>

#include <memory>

#include <mutex>

#include <sstream>

#include <string>

#include <vector>

#include "common/config.h"

#include "gutil/strings/substitute.h"

#include "util/doris_metrics.h"

#include "util/jni_native_method.h"

// #include "util/libjvm_loader.h"

using std::string;

namespace doris {

namespace {

JavaVM* g_vm;

[[maybe_unused]] std::once_flag g_vm_once;

const std::string GetDorisJNIDefaultClasspath() {

    const auto* doris_home = getenv("DORIS_HOME");

    DCHECK(doris_home) << "Environment variable DORIS_HOME is not set.";

    std::ostringstream out;

    auto add_jars_from_path = [&](const std::string& base_path) {

        if (!std::filesystem::exists(base_path)) {

            return;

        }

        for (const auto& entry : std::filesystem::recursive_directory_iterator(base_path)) {

            if (entry.path().extension() == ".jar") {

                if (!out.str().empty()) {

                    out << ":";

                }

                out << entry.path().string();

            }

        }

    };

    add_jars_from_path(std::string(doris_home) + "/lib");

    add_jars_from_path(std::string(doris_home) + "/custom_lib");

    // Check and add HADOOP_CONF_DIR if it's set

    const auto* hadoop_conf_dir = getenv("HADOOP_CONF_DIR");

    if (hadoop_conf_dir != nullptr && strlen(hadoop_conf_dir) > 0) {

        if (!out.str().empty()) {

            out << ":";

        }

        out << hadoop_conf_dir;

    }

    DCHECK(!out.str().empty()) << "Empty classpath is invalid.";

    return out.str();

}

const std::string GetDorisJNIClasspathOption() {

    const auto* classpath = getenv("DORIS_CLASSPATH");

    if (classpath) {

        return classpath;

    } else {

        return "-Djava.class.path=" + GetDorisJNIDefaultClasspath();

    }

}

[[maybe_unused]] void SetEnvIfNecessary() {

    const auto* doris_home = getenv("DORIS_HOME");

    DCHECK(doris_home) << "Environment variable DORIS_HOME is not set.";

    // CLASSPATH

    const std::string original_classpath = getenv("CLASSPATH") ? getenv("CLASSPATH") : "";

    static const std::string classpath = fmt::format(

            "{}/conf:{}:{}", doris_home, GetDorisJNIDefaultClasspath(), original_classpath);

    setenv("CLASSPATH", classpath.c_str(), 0);

    // LIBHDFS_OPTS

    const std::string java_opts = getenv("JAVA_OPTS") ? getenv("JAVA_OPTS") : "";

    std::string libhdfs_opts =

            fmt::format("{} -Djava.library.path={}/lib/hadoop_hdfs/native:{}", java_opts,

                        getenv("DORIS_HOME"), getenv("DORIS_HOME") + std::string("/lib"));

    setenv("LIBHDFS_OPTS", libhdfs_opts.c_str(), 0);

}

// Only used on non-x86 platform

[[maybe_unused]] void FindOrCreateJavaVM() {

    int num_vms;

    int rv = JNI_GetCreatedJavaVMs(&g_vm, 1, &num_vms);

    if (rv == 0) {

        std::vector<std::string> options;

        char* java_opts = getenv("JAVA_OPTS");

        if (java_opts == nullptr) {

            options = {

                    GetDorisJNIClasspathOption(), fmt::format("-Xmx{}", "1g"),

                    fmt::format("-DlogPath={}/log/jni.log", getenv("DORIS_HOME")),

                    fmt::format("-Dsun.java.command={}", "DorisBE"), "-XX:-CriticalJNINatives",

#ifdef __APPLE__

                    // On macOS, we should disable MaxFDLimit, otherwise the RLIMIT_NOFILE

                    // will be assigned the minimum of OPEN_MAX (10240) and rlim_cur (See src/hotspot/os/bsd/os_bsd.cpp)

                    // and it can not pass the check performed by storage engine.

                    // The newer JDK has fixed this issue.

                    "-XX:-MaxFDLimit"

#endif

            };

        } else {

            std::istringstream stream(java_opts);

            options = std::vector<std::string>(std::istream_iterator<std::string> {stream},

                                               std::istream_iterator<std::string>());

            options.push_back(GetDorisJNIClasspathOption());

        }

        std::unique_ptr<JavaVMOption[]> jvm_options(new JavaVMOption[options.size()]);

        for (int i = 0; i < options.size(); ++i) {

            jvm_options[i] = {const_cast<char*>(options[i].c_str()), nullptr};

        }

        JNIEnv* env = nullptr;

        JavaVMInitArgs vm_args;

        vm_args.version = JNI_VERSION_1_8;

        vm_args.options = jvm_options.get();

        vm_args.nOptions = options.size();

        // Set it to JNI_FALSE because JNI_TRUE will let JVM ignore the max size config.

        vm_args.ignoreUnrecognized = JNI_FALSE;

        jint res = JNI_CreateJavaVM(&g_vm, (void**)&env, &vm_args);

        if (JNI_OK != res) {

            DCHECK(false) << "Failed to create JVM, code= " << res;

        }

    } else {

        CHECK_EQ(rv, 0) << "Could not find any created Java VM";

        CHECK_EQ(num_vms, 1) << "No VMs returned";

    }

}

} // anonymous namespace

bool JniUtil::jvm_inited_ = false;

__thread JNIEnv* JniUtil::tls_env_ = nullptr;

jclass JniUtil::internal_exc_cl_ = nullptr;

jclass JniUtil::jni_util_cl_ = nullptr;

jclass JniUtil::jni_native_method_exc_cl_ = nullptr;

jmethodID JniUtil::throwable_to_string_id_ = nullptr;

jmethodID JniUtil::throwable_to_stack_trace_id_ = nullptr;

jmethodID JniUtil::get_jvm_metrics_id_ = nullptr;

jmethodID JniUtil::get_jvm_threads_id_ = nullptr;

jmethodID JniUtil::get_jmx_json_ = nullptr;

jobject JniUtil::jni_scanner_loader_obj_ = nullptr;

jmethodID JniUtil::jni_scanner_loader_method_ = nullptr;

jlong JniUtil::max_jvm_heap_memory_size_ = 0;

jmethodID JniUtil::_clean_udf_cache_method_id = nullptr;

Status JniUtfCharGuard::create(JNIEnv* env, jstring jstr, JniUtfCharGuard* out) {

    DCHECK(jstr != nullptr);

    DCHECK(!env->ExceptionCheck());

    jboolean is_copy;

    const char* utf_chars = env->GetStringUTFChars(jstr, &is_copy);

    bool exception_check = static_cast<bool>(env->ExceptionCheck());

    if (utf_chars == nullptr || exception_check) {

        if (exception_check) env->ExceptionClear();

        if (utf_chars != nullptr) env->ReleaseStringUTFChars(jstr, utf_chars);

        auto fail_message = "GetStringUTFChars failed. Probable OOM on JVM side";

        LOG(WARNING) << fail_message;

        return Status::InternalError(fail_message);

    }

    out->env = env;

    out->jstr = jstr;

    out->utf_chars = utf_chars;

    return Status::OK();

}

Status JniLocalFrame::push(JNIEnv* env, int max_local_ref) {

    DCHECK(env_ == nullptr);

    DCHECK_GT(max_local_ref, 0);

    if (env->PushLocalFrame(max_local_ref) < 0) {

        env->ExceptionClear();

        return Status::InternalError("failed to push frame");

    }

    env_ = env;

    return Status::OK();

}

void JniUtil::parse_max_heap_memory_size_from_jvm(JNIEnv* env) {

    // The start_be.sh would set JAVA_OPTS inside LIBHDFS_OPTS

    std::string java_opts = getenv("LIBHDFS_OPTS") ? getenv("LIBHDFS_OPTS") : "";

    std::istringstream iss(java_opts);

    std::string opt;

    while (iss >> opt) {

        if (opt.find("-Xmx") == 0) {

            std::string xmxValue = opt.substr(4);

            LOG(INFO) << "The max heap vaule is " << xmxValue;

            char unit = xmxValue.back();

            xmxValue.pop_back();

            long long value = std::stoll(xmxValue);

            switch (unit) {

            case 'g':

            case 'G':

                max_jvm_heap_memory_size_ = value * 1024 * 1024 * 1024;

                break;

            case 'm':

            case 'M':

                max_jvm_heap_memory_size_ = value * 1024 * 1024;

                break;

            case 'k':

            case 'K':

                max_jvm_heap_memory_size_ = value * 1024;

                break;

            default:

                max_jvm_heap_memory_size_ = value;

                break;

            }

        }

    }

    if (0 == max_jvm_heap_memory_size_) {

        LOG(FATAL) << "the max_jvm_heap_memory_size_ is " << max_jvm_heap_memory_size_;

    }

    LOG(INFO) << "the max_jvm_heap_memory_size_ is " << max_jvm_heap_memory_size_;

}

size_t JniUtil::get_max_jni_heap_memory_size() {

#if defined(USE_LIBHDFS3) || defined(BE_TEST)

    return std::numeric_limits<size_t>::max();

#else

    static std::once_flag parse_max_heap_memory_size_from_jvm_flag;

    std::call_once(parse_max_heap_memory_size_from_jvm_flag, parse_max_heap_memory_size_from_jvm,

                   tls_env_);

    return max_jvm_heap_memory_size_;

#endif

}

Status JniUtil::GetJNIEnvSlowPath(JNIEnv** env) {

    DCHECK(!tls_env_) << "Call GetJNIEnv() fast path";

#ifdef USE_LIBHDFS3

    std::call_once(g_vm_once, FindOrCreateJavaVM);

    int rc = g_vm->GetEnv(reinterpret_cast<void**>(&tls_env_), JNI_VERSION_1_8);

    if (rc == JNI_EDETACHED) {

        rc = g_vm->AttachCurrentThread((void**)&tls_env_, nullptr);

    }

    if (rc != 0 || tls_env_ == nullptr) {

        return Status::InternalError("Unable to get JVM: {}", rc);

    }

#else

    // the hadoop libhdfs will do all the stuff

    SetEnvIfNecessary();

    tls_env_ = getJNIEnv();

#endif

    *env = tls_env_;

    return Status::OK();

}

Status JniUtil::GetJniExceptionMsg(JNIEnv* env, bool log_stack, const string& prefix) {

    jthrowable exc = env->ExceptionOccurred();

    if (exc == nullptr) {

        return Status::OK();

    }

    env->ExceptionClear();

    DCHECK(throwable_to_string_id() != nullptr);

    const char* oom_msg_template =

            "$0 threw an unchecked exception. The JVM is likely out "

            "of memory (OOM).";

    jstring msg = static_cast<jstring>(

            env->CallStaticObjectMethod(jni_util_class(), throwable_to_string_id(), exc));

    if (env->ExceptionOccurred()) {

        env->ExceptionClear();

        string oom_msg = strings::Substitute(oom_msg_template, "throwableToString");

        LOG(WARNING) << oom_msg;

        return Status::InternalError(oom_msg);

    }

    JniUtfCharGuard msg_str_guard;

    RETURN_IF_ERROR(JniUtfCharGuard::create(env, msg, &msg_str_guard));

    if (log_stack) {

        jstring stack = static_cast<jstring>(

                env->CallStaticObjectMethod(jni_util_class(), throwable_to_stack_trace_id(), exc));

        if (env->ExceptionOccurred()) {

            env->ExceptionClear();

            string oom_msg = strings::Substitute(oom_msg_template, "throwableToStackTrace");

            LOG(WARNING) << oom_msg;

            return Status::InternalError(oom_msg);

        }

        JniUtfCharGuard c_stack_guard;

        RETURN_IF_ERROR(JniUtfCharGuard::create(env, stack, &c_stack_guard));

        LOG(WARNING) << c_stack_guard.get();

    }

    env->DeleteLocalRef(exc);

    return Status::InternalError("{}{}", prefix, msg_str_guard.get());

}

jobject JniUtil::convert_to_java_map(JNIEnv* env, const std::map<std::string, std::string>& map) {

    //TODO: ADD EXCEPTION CHECK.

    jclass hashmap_class = env->FindClass("java/util/HashMap");

    jmethodID hashmap_constructor = env->GetMethodID(hashmap_class, "<init>", "(I)V");

    jobject hashmap_object = env->NewObject(hashmap_class, hashmap_constructor, map.size());

    jmethodID hashmap_put = env->GetMethodID(

            hashmap_class, "put", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;");

    for (const auto& it : map) {

        jstring key = env->NewStringUTF(it.first.c_str());

        jstring value = env->NewStringUTF(it.second.c_str());

        env->CallObjectMethod(hashmap_object, hashmap_put, key, value);

        env->DeleteLocalRef(key);

        env->DeleteLocalRef(value);

    }

    env->DeleteLocalRef(hashmap_class);

    return hashmap_object;

}

std::map<std::string, std::string> JniUtil::convert_to_cpp_map(JNIEnv* env, jobject map) {

    std::map<std::string, std::string> resultMap;

    // Get the class and method ID of the java.util.Map interface

    jclass mapClass = env->FindClass("java/util/Map");

    jmethodID entrySetMethod = env->GetMethodID(mapClass, "entrySet", "()Ljava/util/Set;");

    // Get the class and method ID of the java.util.Set interface

    jclass setClass = env->FindClass("java/util/Set");

    jmethodID iteratorSetMethod = env->GetMethodID(setClass, "iterator", "()Ljava/util/Iterator;");

    // Get the class and method ID of the java.util.Iterator interface

    jclass iteratorClass = env->FindClass("java/util/Iterator");

    jmethodID hasNextMethod = env->GetMethodID(iteratorClass, "hasNext", "()Z");

    jmethodID nextMethod = env->GetMethodID(iteratorClass, "next", "()Ljava/lang/Object;");

    // Get the class and method ID of the java.util.Map.Entry interface

    jclass entryClass = env->FindClass("java/util/Map$Entry");

    jmethodID getKeyMethod = env->GetMethodID(entryClass, "getKey", "()Ljava/lang/Object;");

    jmethodID getValueMethod = env->GetMethodID(entryClass, "getValue", "()Ljava/lang/Object;");

    // Call the entrySet method to get the set of key-value pairs

    jobject entrySet = env->CallObjectMethod(map, entrySetMethod);

    // Call the iterator method on the set to iterate over the key-value pairs

    jobject iteratorSet = env->CallObjectMethod(entrySet, iteratorSetMethod);

    // Iterate over the key-value pairs

    while (env->CallBooleanMethod(iteratorSet, hasNextMethod)) {

        // Get the current entry

        jobject entry = env->CallObjectMethod(iteratorSet, nextMethod);

        // Get the key and value from the entry

        jobject javaKey = env->CallObjectMethod(entry, getKeyMethod);

        jobject javaValue = env->CallObjectMethod(entry, getValueMethod);

        // Convert the key and value to C++ strings

        const char* key = env->GetStringUTFChars(static_cast<jstring>(javaKey), nullptr);

        const char* value = env->GetStringUTFChars(static_cast<jstring>(javaValue), nullptr);

        // Store the key-value pair in the map

        resultMap[key] = value;

        // Release the string references

        env->ReleaseStringUTFChars(static_cast<jstring>(javaKey), key);

        env->ReleaseStringUTFChars(static_cast<jstring>(javaValue), value);

        // Delete local references

        env->DeleteLocalRef(entry);

        env->DeleteLocalRef(javaKey);

        env->DeleteLocalRef(javaValue);

    }

    // Delete local references

    env->DeleteLocalRef(iteratorSet);

    env->DeleteLocalRef(entrySet);

    env->DeleteLocalRef(mapClass);

    env->DeleteLocalRef(setClass);

    env->DeleteLocalRef(iteratorClass);

    env->DeleteLocalRef(entryClass);

    return resultMap;

}

Status JniUtil::GetGlobalClassRef(JNIEnv* env, const char* class_str, jclass* class_ref) {

    *class_ref = NULL;

    JNI_CALL_METHOD_CHECK_EXCEPTION_DELETE_REF(jclass, local_cl, env, FindClass(class_str));

    RETURN_IF_ERROR(LocalToGlobalRef(env, local_cl, reinterpret_cast<jobject*>(class_ref)));

    return Status::OK();

}

Status JniUtil::LocalToGlobalRef(JNIEnv* env, jobject local_ref, jobject* global_ref) {

    *global_ref = env->NewGlobalRef(local_ref);

    // NewGlobalRef:

    // Returns a global reference to the given obj.

    //

    //May return NULL if:

    //  obj refers to null

    //  the system has run out of memory

    //  obj was a weak global reference and has already been garbage collected

    if (*global_ref == NULL) {

        return Status::InternalError(

                "LocalToGlobalRef fail,global ref is NULL,maybe the system has run out of memory.");

    }

    //NewGlobalRef not throw exception,maybe we just need check NULL.

    RETURN_ERROR_IF_EXC(env);

    return Status::OK();

}

Status JniUtil::init_jni_scanner_loader(JNIEnv* env) {

    // Get scanner loader;

    jclass jni_scanner_loader_cls;

    std::string jni_scanner_loader_str = "org/apache/doris/common/classloader/ScannerLoader";

    RETURN_IF_ERROR(JniUtil::GetGlobalClassRef(env, jni_scanner_loader_str.c_str(),

                                               &jni_scanner_loader_cls));

    jmethodID jni_scanner_loader_constructor =

            env->GetMethodID(jni_scanner_loader_cls, "<init>", "()V");

    RETURN_ERROR_IF_EXC(env);

    jni_scanner_loader_method_ = env->GetMethodID(jni_scanner_loader_cls, "getLoadedClass",

                                                  "(Ljava/lang/String;)Ljava/lang/Class;");

    if (jni_scanner_loader_method_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find ScannerLoader.getLoadedClass method.");

    }

    RETURN_ERROR_IF_EXC(env);

    jmethodID load_jni_scanner =

            env->GetMethodID(jni_scanner_loader_cls, "loadAllScannerJars", "()V");

    RETURN_ERROR_IF_EXC(env);

    jni_scanner_loader_obj_ =

            env->NewObject(jni_scanner_loader_cls, jni_scanner_loader_constructor);

    RETURN_ERROR_IF_EXC(env);

    if (jni_scanner_loader_obj_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to create ScannerLoader object.");

    }

    env->CallVoidMethod(jni_scanner_loader_obj_, load_jni_scanner);

    RETURN_ERROR_IF_EXC(env);

    _clean_udf_cache_method_id = env->GetMethodID(jni_scanner_loader_cls, "cleanUdfClassLoader",

                                                  "(Ljava/lang/String;)V");

    if (_clean_udf_cache_method_id == nullptr) {

        if (env->ExceptionOccurred()) {

            env->ExceptionDescribe();

        }

        return Status::InternalError("Failed to find removeUdfClassLoader method.");

    }

    RETURN_ERROR_IF_EXC(env);

    return Status::OK();

}

Status JniUtil::clean_udf_class_load_cache(const std::string& function_signature) {

    JNIEnv* env = nullptr;

    RETURN_IF_ERROR(JniUtil::GetJNIEnv(&env));

    env->CallVoidMethod(jni_scanner_loader_obj_, _clean_udf_cache_method_id,

                        env->NewStringUTF(function_signature.c_str()));

    RETURN_ERROR_IF_EXC(env);

    return Status::OK();

}

Status JniUtil::get_jni_scanner_class(JNIEnv* env, const char* classname,

                                      jclass* jni_scanner_class) {

    // Get JNI scanner class by class name;

    jobject loaded_class_obj = env->CallObjectMethod(

            jni_scanner_loader_obj_, jni_scanner_loader_method_, env->NewStringUTF(classname));

    RETURN_ERROR_IF_EXC(env);

    *jni_scanner_class = reinterpret_cast<jclass>(env->NewGlobalRef(loaded_class_obj));

    RETURN_ERROR_IF_EXC(env);

    return Status::OK();

}

Status JniUtil::Init() {

    // RETURN_IF_ERROR(LibJVMLoader::instance().load());

    // Get the JNIEnv* corresponding to current thread.

    JNIEnv* env = nullptr;

    RETURN_IF_ERROR(JniUtil::GetJNIEnv(&env));

    if (env == NULL) return Status::InternalError("Failed to get/create JVM");

    // Find JniUtil class and create a global ref.

    jclass local_jni_util_cl = env->FindClass("org/apache/doris/common/jni/utils/JniUtil");

    if (local_jni_util_cl == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil class.");

    }

    jni_util_cl_ = reinterpret_cast<jclass>(env->NewGlobalRef(local_jni_util_cl));

    if (jni_util_cl_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to create global reference to JniUtil class.");

    }

    env->DeleteLocalRef(local_jni_util_cl);

    if (env->ExceptionOccurred()) {

        return Status::InternalError("Failed to delete local reference to JniUtil class.");

    }

    // Find InternalException class and create a global ref.

    jclass local_internal_exc_cl =

            env->FindClass("org/apache/doris/common/exception/InternalException");

    if (local_internal_exc_cl == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil class.");

    }

    internal_exc_cl_ = reinterpret_cast<jclass>(env->NewGlobalRef(local_internal_exc_cl));

    if (internal_exc_cl_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to create global reference to JniUtil class.");

    }

    env->DeleteLocalRef(local_internal_exc_cl);

    if (env->ExceptionOccurred()) {

        return Status::InternalError("Failed to delete local reference to JniUtil class.");

    }

    // Find JNINativeMethod class and create a global ref.

    jclass local_jni_native_exc_cl =

            env->FindClass("org/apache/doris/common/jni/utils/JNINativeMethod");

    if (local_jni_native_exc_cl == nullptr) {

        if (env->ExceptionOccurred()) {

            env->ExceptionDescribe();

        }

        return Status::InternalError("Failed to find JNINativeMethod class.");

    }

    jni_native_method_exc_cl_ =

            reinterpret_cast<jclass>(env->NewGlobalRef(local_jni_native_exc_cl));

    if (jni_native_method_exc_cl_ == nullptr) {

        if (env->ExceptionOccurred()) {

            env->ExceptionDescribe();

        }

        return Status::InternalError("Failed to create global reference to JNINativeMethod class.");

    }

    env->DeleteLocalRef(local_jni_native_exc_cl);

    if (env->ExceptionOccurred()) {

        return Status::InternalError("Failed to delete local reference to JNINativeMethod class.");

    }

    std::string resize_column_name = "resizeStringColumn";

    std::string resize_column_sign = "(JI)J";

    std::string memory_alloc_name = "memoryTrackerMalloc";

    std::string memory_alloc_sign = "(J)J";

    std::string memory_free_name = "memoryTrackerFree";

    std::string memory_free_sign = "(J)V";

    static JNINativeMethod java_native_methods[] = {

            {const_cast<char*>(resize_column_name.c_str()),

             const_cast<char*>(resize_column_sign.c_str()),

             (void*)&JavaNativeMethods::resizeStringColumn},

            {const_cast<char*>(memory_alloc_name.c_str()),

             const_cast<char*>(memory_alloc_sign.c_str()), (void*)&JavaNativeMethods::memoryMalloc},

            {const_cast<char*>(memory_free_name.c_str()),

             const_cast<char*>(memory_free_sign.c_str()), (void*)&JavaNativeMethods::memoryFree},

    };

    int res = env->RegisterNatives(jni_native_method_exc_cl_, java_native_methods,

                                   sizeof(java_native_methods) / sizeof(java_native_methods[0]));

    DCHECK_EQ(res, 0);

    // Throwable toString()

    throwable_to_string_id_ = env->GetStaticMethodID(jni_util_cl_, "throwableToString",

                                                     "(Ljava/lang/Throwable;)Ljava/lang/String;");

    if (throwable_to_string_id_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil.throwableToString method.");

    }

    // throwableToStackTrace()

    throwable_to_stack_trace_id_ = env->GetStaticMethodID(

            jni_util_cl_, "throwableToStackTrace", "(Ljava/lang/Throwable;)Ljava/lang/String;");

    if (throwable_to_stack_trace_id_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil.throwableToFullStackTrace method.");

    }

    get_jvm_metrics_id_ = env->GetStaticMethodID(jni_util_cl_, "getJvmMemoryMetrics", "()[B");

    if (get_jvm_metrics_id_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil.getJvmMemoryMetrics method.");

    }

    get_jvm_threads_id_ = env->GetStaticMethodID(jni_util_cl_, "getJvmThreadsInfo", "([B)[B");

    if (get_jvm_threads_id_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil.getJvmThreadsInfo method.");

    }

    get_jmx_json_ = env->GetStaticMethodID(jni_util_cl_, "getJMXJson", "()[B");

    if (get_jmx_json_ == NULL) {

        if (env->ExceptionOccurred()) env->ExceptionDescribe();

        return Status::InternalError("Failed to find JniUtil.getJMXJson method.");

    }

    RETURN_IF_ERROR(init_jni_scanner_loader(env));

    jvm_inited_ = true;

    DorisMetrics::instance()->init_jvm_metrics(env);

    return Status::OK();

}

} // namespace doris