java可以开启线程吗？

答：不可以

原因：java运行在虚拟机上，无法直接操作硬件，在start方法中调用了本地方法start0()，这是一个通过C++操作的方法。

底层源码：

package java.lang;

public class Thread implements Runnable {
  
  
    public synchronized void start() {
      /**
       * This method is not invoked for the main method thread or "system"
       * group threads created/set up by the VM. Any new functionality added
       * to this method in the future may have to also be added to the VM.
       *
       * A zero status value corresponds to state "NEW".
       */
      if (threadStatus != 0)
          throw new IllegalThreadStateException();

      /* Notify the group that this thread is about to be started
       * so that it can be added to the group's list of threads
       * and the group's unstarted count can be decremented. */
      group.add(this);

      boolean started = false;
      try {
          start0();
          started = true;
      } finally {
          try {
              if (!started) {
                  group.threadStartFailed(this);
              }
          } catch (Throwable ignore) {
              /* do nothing. If start0 threw a Throwable then
                it will be passed up the call stack */
          }
      }
  }
 
	private native void start0();
  
}