目录

• 
  Thread类里有一个本地方法叫registerNatives，此方法注册一些本地方法给Thread类使用
  在OpenJDK官网找到Thread.c

  #include "jni.h" #include "jvm.h"  #include "java_lang_Thread.h"  #define THD "Ljava/lang/Thread;" #define OBJ "Ljava/lang/Object;" #define STE "Ljava/lang/StackTraceElement;"  #define ARRAY_LENGTH(a) (sizeof(a)/sizeof(a[0]))  static JNINativeMethod methods[] = {     {"start0",           "()V",        (void *)&JVM_StartThread}, //Java中Thread类的start方法所调用的start0方法     {"stop0",            "(" OBJ ")V", (void *)&JVM_StopThread},     {"isAlive",          "()Z",        (void *)&JVM_IsThreadAlive},     {"suspend0",         "()V",        (void *)&JVM_SuspendThread},     {"resume0",          "()V",        (void *)&JVM_ResumeThread},     {"setPriority0",     "(I)V",       (void *)&JVM_SetThreadPriority},     {"yield",            "()V",        (void *)&JVM_Yield},     {"sleep",            "(J)V",       (void *)&JVM_Sleep},     {"currentThread",    "()" THD,     (void *)&JVM_CurrentThread},     {"countStackFrames", "()I",        (void *)&JVM_CountStackFrames},     {"interrupt0",       "()V",        (void *)&JVM_Interrupt},     {"isInterrupted",    "(Z)Z",       (void *)&JVM_IsInterrupted},     {"holdsLock",        "(" OBJ ")Z", (void *)&JVM_HoldsLock},     {"getThreads",        "()[" THD,   (void *)&JVM_GetAllThreads},     {"dumpThreads",      "([" THD ")[[" STE, (void *)&JVM_DumpThreads}, };  ......

  根据关键字"JVM_StartThread"再找到jvm.cpp

  JVM_ENTRY(void, JVM_StartThread(JNIEnv* env, jobject jthread))   JVMWrapper("JVM_StartThread");   JavaThread *native_thread = NULL;   bool throw_illegal_thread_state = false;    {     MutexLocker mu(Threads_lock);     if (java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)) != NULL) {       throw_illegal_thread_state = true;     } else {        jlong size =              java_lang_Thread::stackSize(JNIHandles::resolve_non_null(jthread));       size_t sz = size > 0 ? (size_t) size : 0;       native_thread = new JavaThread(&thread_entry, sz); //请看这里，实例化了一个线程native_thread        if (native_thread->osthread() != NULL) {         // Note: the current thread is not being used within "prepare".         native_thread->prepare(jthread);       }     }   }

  sz是大小参数，忽略之，我们看thread_entry是什么