path: root/java/jni/helper_base.hpp

/*
 * Author: Andrei Vasiliu <andrei.vasiliu@intel.com>
 * Copyright (c) 2016 Intel Corporation.
 *
 * Author: Sven Gothel <sgothel@jausoft.com>
 * Copyright (c) 2020 Gothel Software e.K.
 * Copyright (c) 2020 ZAFENA AB
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef HELPER_BASE_HPP_
#define HELPER_BASE_HPP_

#include <vector>
#include <memory>
#include <functional>
#include <jni.h>

#include "BasicTypes.hpp"

/**
 * Return true if a java exception occurred, otherwise false.
 * <p>
 * In case of an exception, the information might be logged to stderr.
 * </p>
 * <p>
 * In case of an exception, user shall release resourced in their JNI code
 * and leave immediately.
 * </p>
 */
bool java_exception_check(JNIEnv *env, const char* file, int line);

/**
 * Throws a C++ exception if a java exception occurred, otherwise do nothing.
 * <p>
 * In case of an exception, the information might be logged to stderr.
 * </p>
 * <p>
 * In case of an exception and hence thrown C++ exception,
 * might want to catch all and handle it via {@link #rethrow_and_raise_java_exception(JNIEnv*)}.
 * </p>
 */
void java_exception_check_and_throw(JNIEnv *env, const char* file, int line);


jfieldID getField(JNIEnv *env, jobject obj, const char* field_name, const char* field_signature);
inline jfieldID getInstanceField(JNIEnv *env, jobject obj) {
    return getField(env, obj, "nativeInstance", "J");
}

jclass search_class(JNIEnv *env, const char *clazz_name);
jclass search_class(JNIEnv *env, jobject obj);
jmethodID search_method(JNIEnv *env, jclass clazz, const char *method_name,
                        const char *prototype, bool is_static);
jfieldID search_field(JNIEnv *env, jclass clazz, const char *field_name,
                        const char *type, bool is_static);
bool from_jboolean_to_bool(jboolean val);
std::string from_jstring_to_string(JNIEnv *env, jstring str);
jstring from_string_to_jstring(JNIEnv *env, const std::string & str);
jobject get_bluetooth_type(JNIEnv *env, const char *field_name);
jobject get_new_arraylist(JNIEnv *env, unsigned int size, jmethodID *add);

template <typename T>
T *castInstance(jlong instance)
{
    T *t = reinterpret_cast<T *>(instance);
    if (t == nullptr) {
        throw std::runtime_error("Trying to cast null object");
    }
    return t;
}

template <typename T>
T *getObjectRef(JNIEnv *env, jobject obj, const char* field_name)
{
    jlong jobj = env->GetLongField(obj, getField(env, obj, field_name, "J"));
    java_exception_check_and_throw(env, E_FILE_LINE);
    return reinterpret_cast<T *>(jobj);
}

template <typename T>
void setObjectRef(JNIEnv *env, jobject obj, T *t, const char* field_name)
{
    jlong jobj = reinterpret_cast<jlong>(t);
    env->SetLongField(obj, getField(env, obj, field_name, "J"), jobj);
    java_exception_check_and_throw(env, E_FILE_LINE);
}

template <typename T>
T *getInstance(JNIEnv *env, jobject obj)
{
    jlong instance = env->GetLongField(obj, getInstanceField(env, obj));
    T *t = reinterpret_cast<T *>(instance);
    if (t == nullptr) {
        throw std::runtime_error("Trying to acquire null object");
    }
    return t;
}

template <typename T>
T *getInstanceUnchecked(JNIEnv *env, jobject obj)
{
    jlong instance = env->GetLongField(obj, getInstanceField(env, obj));
    return reinterpret_cast<T *>(instance);
}

template <typename T>
void setInstance(JNIEnv *env, jobject obj, T *t)
{
    if (t == nullptr) {
        throw std::runtime_error("Trying to create null object");
    }
    jlong instance = reinterpret_cast<jlong>(t);
    env->SetLongField(obj, getInstanceField(env, obj), instance);
}

template <typename T>
jobject generic_clone(JNIEnv *env, jobject obj)
{
    T *obj_generic = getInstance<T>(env, obj);
    T *copy_generic = obj_generic->clone();

    jclass generic_class = search_class(env, *copy_generic);
    jmethodID generic_ctor = search_method(env, generic_class, "<init>", "(J)V", false);

    jobject result = env->NewObject(generic_class, generic_ctor, (jlong)copy_generic);
    if (!result)
    {
        throw std::runtime_error("cannot create instance of class");
    }

    return result;
}

template <typename T>
jobject convert_vector_uniqueptr_to_jarraylist(JNIEnv *env, std::vector<std::unique_ptr<T>>& array,
        const char *ctor_prototype)
{
    unsigned int array_size = array.size();

    jmethodID arraylist_add;
    jobject result = get_new_arraylist(env, array_size, &arraylist_add);

    if (array_size == 0)
    {
        return result;
    }

    jclass clazz = search_class(env, T::java_class().c_str());
    jmethodID clazz_ctor = search_method(env, clazz, "<init>", ctor_prototype, false);

    for (unsigned int i = 0; i < array_size; ++i)
    {
        T *elem = array[i].release();
        jobject object = env->NewObject(clazz, clazz_ctor, (jlong)elem);
        if (!object)
        {
            throw direct_bt::InternalError("cannot create instance of class", E_FILE_LINE);
        }
        env->CallBooleanMethod(result, arraylist_add, object);
    }
    return result;
}

template <typename T>
jobject convert_vector_uniqueptr_to_jarraylist(JNIEnv *env, std::vector<std::unique_ptr<T>>& array,
        const char *ctor_prototype, std::function<jobject(JNIEnv*, jclass, jmethodID, T*)> ctor)
{
    unsigned int array_size = array.size();

    jmethodID arraylist_add;
    jobject result = get_new_arraylist(env, array_size, &arraylist_add);

    if (array_size == 0)
    {
        return result;
    }

    jclass clazz = search_class(env, T::java_class().c_str());
    jmethodID clazz_ctor = search_method(env, clazz, "<init>", ctor_prototype, false);

    for (unsigned int i = 0; i < array_size; ++i)
    {
        T *elem = array[i].release();
        jobject object = ctor(env, clazz, clazz_ctor, elem);
        if (!object)
        {
            throw std::runtime_error("cannot create instance of class\n");
        }
        env->CallBooleanMethod(result, arraylist_add, object);
    }
    return result;
}

template <typename T>
jobject convert_vector_sharedptr_to_jarraylist(JNIEnv *env, std::vector<std::shared_ptr<T>>& array,
        const char *ctor_prototype, std::function<jobject(JNIEnv*, jclass, jmethodID, T*)> ctor)
{
    unsigned int array_size = array.size();

    jmethodID arraylist_add;
    jobject result = get_new_arraylist(env, array_size, &arraylist_add);

    if (array_size == 0)
    {
        return result;
    }

    jclass clazz = search_class(env, T::java_class().c_str());
    jmethodID clazz_ctor = search_method(env, clazz, "<init>", ctor_prototype, false);

    for (unsigned int i = 0; i < array_size; ++i)
    {
        T *elem = array[i].get();
        jobject object = ctor(env, clazz, clazz_ctor, elem);
        if (!object)
        {
            throw std::runtime_error("cannot create instance of class\n");
        }
        env->CallBooleanMethod(result, arraylist_add, object);
    }
    return result;
}

void raise_java_exception(JNIEnv *env, std::exception &e);
void raise_java_runtime_exception(JNIEnv *env, std::runtime_error &e);
void raise_java_runtime_exception(JNIEnv *env, direct_bt::RuntimeException &e);
void raise_java_oom_exception(JNIEnv *env, std::bad_alloc &e);
void raise_java_invalid_arg_exception(JNIEnv *env, std::invalid_argument &e);
void raise_java_bluetooth_exception(JNIEnv *env, direct_bt::BluetoothException &e);

/**
 * Re-throw current exception and raise respective java exception
 * using any matching function above.
 */
void rethrow_and_raise_java_exception(JNIEnv *env);

#endif /* HELPER_BASE_HPP_ */