JMI

    // 在任意 jmi::JObject<SurfaceTexture> 可见范围内定义 SurfaceTexture tag 类
    struct SurfaceTexture : jmi::ClassTag { static constexpr auto name() {return JMISTRM("android/graphics/SurfaceTexture");}}; // 或 JMISTR("android.graphics.SurfaceTexture")
    ...
    GLuint tex = ...
    ...
    jmi::JObject<SurfaceTexture> texture;
    if (!texture.create(tex)) {
        // texture.error() ...
    }

    struct Surface : jmi::ClassTag { static constexpr auto name() {return JMISTR("android.view.Surface");}}; // '.' or '/'
    ...
    jmi::JObject<Surface> surface;
    surface.create(texture);

    texture.call("updateTexImage");

    texture.call<void>("updateTexImage");

    float mat4[16]; // or std::array<float, 16>, valarray<float>
    texture.call("getTransformMatrix", std::ref(mat4)); // use std::ref() if parameter should be modified by jni method

    MediaCodec::BufferInfo bi;
    bi.create();
    codec.dequeueOutputBuffer(bi, timeout); // bi is of type MediaCodec::BufferInfo&

    auto t = texture.call<jlong>("getTimestamp");

    // GetMethodID() 对于每个不同的方法只会被调用一次
    struct UpdateTexImage : jmi::MethodTag { static const char* name() {return "updateTexImage";}};
    struct GetTimestamp : jmi::MethodTag { static const char* name() {return "getTimestamp";}};
    struct GetTransformMatrix : jmi::MethodTag { static const char* name() {return "getTransformMatrix";}};
    ...
    texture.call<UpdateTexImage>(); // or texture.call<void,UpdateTexImage>();
    auto t = texture.call<jlong, GetTimestamp>();
    texture.call<GetTransformMatrix>(std::ref(mat4)); // use std::ref() if parameter should be modified by jni method

    JObject<MyClassTag> obj;
    ...
    struct MyIntField : FieldTag { static const char* name() {return "myIntFieldName";} };
    auto ifield = obj.field<jint, MyIntField>();
    jfieldID ifid = ifield; // 或 ifield.id()
    ifield.set(1234);
    jint ivalue = ifield; // 或 ifield.get();

    // 静态 field 也一样，除了使用的是静态方法 JObject::staticField
    struct MyStrFieldS : FieldTag { static const char* name() {return "myStaticStrFieldName";} };
    auto& ifields = JObject<MyClassTag>::staticField<std::string, MyIntFieldS>(); // it can be an ref
    jfieldID ifids = ifields; // 或 ifield.id()
    ifields.set("JMI static field test");
    ifields = "assign";
    std::string ivalues = ifields; // 或 ifield.get();

    auto ifield = obj.field<jint>("myIntFieldName");
    ...

    void native_test_impl(JNIEnv *env , jobject thiz, ...) {}

    staitc const JNINativeMethod gMethods[] = {
        {"native_test", signature_of(native_test_impl).data(), native_test_impl},
        ...
    };

    #define DEFINE_METHOD(M) {#M, signature_of(M##_impl).data(), M##_impl}
    staitc const JNINativeMethod gMethods[] = {
        DEFINE_METHOD(native_test),
        ...
    }