Android 源码关键类路径

1.SystemServer:frameworks\base\services\java\com\android\server

2.ServiceManager:\frameworks\base\core\java\android\os

3.com_android_server_SystemServer（对应SystemServer.java）：\frameworks\base\services\jni(frameworks\base\services\java\com\android\server 看到的service中native方法实现)

4.jni注册native函数

static JNINativeMethod method_table[] = {
    { "init_native", "()I", (void*)init_native },
    { "finalize_native", "(I)V", (void*)finalize_native },
    { "setLight_native", "(IIIIIII)V", (void*)setLight_native },
};

int register_android_server_LightsService(JNIEnv *env)
{
    return jniRegisterNativeMethods(env, "com/android/server/LightsService",
            method_table, NELEM(method_table));
}