无法理解这个 UnsatisfiedLinkError

Question

为 C SDL 库创建 java 包装器时出现此异常：

Exception in thread "main" java.lang.UnsatisfiedLinkError: com.sdl4j.renderer.SDL_Renderer.SDL_CreateRenderer(Lcom/sdl4j/window/SDL_Window;II)Lcom/sdl4j/renderer/SDL_Renderer;

Java 调用者（第一种方法完成得很好并且在 java/c++ 两边看起来 100% 相似）：

    SDL_Window win = SDL_CreateWindow("Hello World!", 0, 0, 1024, 768, SDL_WindowFlags.SDL_WINDOW_SHOWN);
    SDL_Renderer ren = SDL_CreateRenderer(win, -1, SDL_RendererFlags.SDL_RENDERER_ACCELERATED | SDL_RendererFlags.SDL_RENDERER_PRESENTVSYNC);

原生Java函数：

public static native SDL_Renderer SDL_CreateRenderer(SDL_Window window, int index, int flags);

C header:

* Class:     com_sdl4j_renderer_SDL_Renderer
* Method:    SDL_CreateRenderer
* Signature:    (Lcom/sdl4j/window/SDL_Window;II)Lcom/sdl4j/renderer/SDL_Renderer;
*/
JNIEXPORT jobject JNICALL     Java_com_sdl4j_renderer_SDL_1Renderer_SDL_1CreateRenderer
(JNIEnv *, jclass, jobject, jint, jint);

C++ 实现：

JNIEXPORT jobject JNICALL    Java_com_sdl4j_renderer_SDL_1Renderer_SDL_1CreateRenderer(JNIEnv *env, jclass ,    jobject win, jint index, jint flags) {

cout << "Create renderer: " << endl;
}

不明白为什么它不起作用，请你帮忙。

干杯

Answer 1

如果您有重载方法，则需要有 "full" JNI 方法名称。
方法名还应包括参数类型（以便 JNI 区分重载方法）

JNIEXPORT jobject JNICALL     Java_com_sdl4j_renderer_SDL_1Renderer_SDL_1CreateRenderer__Lcom_sdl4j_window_SDL_1Window_2II
(JNIEnv *, jclass, jobject, jint, jint);

从技术上讲，它是相同的方法名称，然后添加 2 个下划线和参数类型。

_      = /
_1     = _
_2     = ;
_00024 = $

无法理解这个 UnsatisfiedLinkError

Can't understand this UnsatisfiedLinkError

java

java-native-interface