Java multi-thread understanding, dark horse programmer, java Dark Horse

Java multi-thread understanding, dark horse programmer, java Dark Horse

Public class MultiThread {public static void main (String args []) {System. out. println ("I am the main thread! "); // Create a thread instance thread1 ThreadUseExtends thread1 = new ThreadUseExtends () below (); // when thread2 is created, Thread thread2 = new Thread (new ThreadUseRunnable (), "SecondThread"); thread1.start (); // start the thread thread1 to make it ready // thread1.setPriority (6); // set the priority of thread1 to 6 // The priority will determine when the cpu is idle, the ready thread who occupies the cpu first starts to run // priority range: 1 to 10, MIN_PRIORITY, MAX_PRIORITY, norm_priority ority // The New thread inherits the priority of the parent thread created for her, the parent thread usually has a common priority of 5NORM_PRIORI. TY System. out. println ("the main thread will be suspended for 7 seconds! "); Try {Thread. sleep (7000); // The main thread suspends for 7 seconds} catch (InterruptedException e) {return;} System. out. println ("back to the main thread! "); If (thread1.isAlive () {thread1.stop (); // if thread1 still exists, kill System. out. println (" thread1 sleep too long, and the main thread kills thread1! ");} Else System. out. println (" thread1 is not found in the main thread. thread1 is awake and the execution is finished! "); Thread2.start (); // start thread2 System. out. println (" the main thread will be suspended for another 7 seconds! "); Try {Thread. sleep (7000); // The main thread suspends for 7 seconds} catch (InterruptedException e) {return;} System. out. println ("back to the main thread! "); If (thread2.isAlive () {thread2.stop (); // if thread2 still exists, kill System. out. println (" thread2 sleep too long, and the main thread kills thread2! ");} Else System. out. println (" thread2 is not found in the main thread. thread2 is awake and the execution is finished! "); System. out. println (" press any key to continue after the program ends! "); Try {System. in. read ();} catch (IOException e) {System. out. println (e. toString () ;}// main} // MultiThreadclass ThreadUseExtends extends Thread // inherits the Thread class and implements its abstract method run () // create an instance of this Thread subclass as appropriate to implement the multithreading mechanism // once a Thread is started (that is, it enters the ready state), its run () will be automatically called once the CPU is obtained () method {ThreadUseExtends () {}// constructor public void run () {System. out. println ("I Am a Thread sub-class Thread instance! "); System. out. println (" I will suspend for 10 seconds! "); System. out. println (" return to the main thread. Please wait. The main thread has been suspended! "); Try {sleep (10000); // suspend for 5 seconds} catch (InterruptedException e) {return ;}// if the run () method is executed in sequence, the thread will automatically end without being killed by the main thread. // However, if the sleep duration is too long, the thread will survive and may be stopped () kill} class ThreadUseRunnable implements Runnable // implement the run () method in the Runnable interface, and then implement the run () method class // The Thread instance for creating the Thread for the parameter {// Thread thread2 = new Thread (this); // run () in the Runnable interface () threadUseRunnable () {}// constructor public void run () {System. out. println ("I Am a Thread instance and take the class that implements the Runnable interface as the parameter! "); System. out. println (" I will suspend for 1 second! "); System. out. println (" back to the main thread, please wait for the jn0-120 e20-040, just the main thread suspended may not wake up! "); Try {Thread. sleep (1000); // suspend for 5 seconds} catch (InterruptedException e) {return;} // If the run () method is executed in sequence, the thread ends automatically, instead of being killed by the main thread. // However, if the sleep duration is too long, the thread remains alive and may be stopped () kill} // modifications to be made to the program, such as modifying the sleep time or priority setPriorit