Java timer usage, daemon thread.

Package CN. vicky; </P> <p> Import Java. util. timer; </P> <p>/** <br/> * Timer: implements the timer mbean. The timer mbean sends a warning at the specified time to wake up all registered listeners to receive timer notifications. This class manages a list of expired timer notifications. <Br/> * This is a method that allows users to add or remove notifications as needed. When the timer sends a timer notification and expires, the notification is automatically removed from the timer notification list. You can add other timer notifications to notifications that are repeatedly sent. <Br/> */<br/> public class mytimer {</P> <p> Public static void main (string [] ARGs) {<br/> timer = new timer (); <br/> // run this task after 1 second. The interval is 2 seconds. If you pass a data parameter, you can execute this task at a fixed time. <br/> timer. schedule (New mytask (), 1000,200 0); <br/> // This is used to stop this task, otherwise, the task will be executed cyclically. <br/> try {<br/> thread. sleep (10000); <br/>} catch (interruptedexception e) {<br/> E. printstacktrace (); <br/>}< br/> // use this method to exit the task <br/> timer. cancel (); <Br/>}</P> <p> static class mytask extends Java. util. timertask {<br/> @ override <br/> Public void run () {<br/> system. out. println ("done! "); <Br/>}< br/>

Done!
Done!
Done!
Done!
......

 

 

The implementation of the daemon thread. This is a good and powerful timer function!

Package CN. vicky; </P> <p> Import Java. util. timer; <br/> Import Java. util. timertask; </P> <p> public class mytimer2 {</P> <p> private string name; <br/> private long timeout; </P> <p> private thread; </P> <p> Public mytimer2 (string name, long timeout) {<br/> This. name = Name; <br/> This. timeout = timeout; <br/>}</P> <p>/** <br/> * when the processing thread of a node consumes too long, the timer will call {@ link system # exit system. exit} method to force the transaction processing thread of the node to close. This timer is a daemon process. <br/> * therefore, when a service is properly closed, the task does not run this program. <Br/> */<br/> Public void startshutdowntimeout (long timeout) {<br/> New timer (true ). schedule (New timertask () {// true, indicating that the thread to be executed is a daemon thread <br/> @ override <br/> Public void run () {<br/> system. out. println ("Thread" + name + "times out and executes the daemon thread! "); <Br/> // system. exit (1); <br/> thread. stop (); <br/>}< br/>}, timeout); <br/>}</P> <p> Public void mytest () {<br/> thread = new thread () {<br/> @ override <br/> Public void run () {<br/> startshutdowntimeout (timeout ); // This thread is played by the daemon. <br/> system. out. println (name + "begin"); <br/> try {<br/> thread. sleep (200); // The function must be executed for at least 200 milliseconds <br/>} catch (interruptedexception e) {<br/> E. printstacktrace (); <br/>}< br/> system. out. println (name + "over"); <br/>}< br/>}; <br/> thread. start (); <br/>}</P> <p> Public static void main (string [] ARGs) {<br/> mytimer2 M1 = new mytimer2 ("1-", 100); <br/> mytimer 2 m2 = new mytimer2 ("2-", 180 ); <br/> mytimer 2 m3 = new mytimer2 ("3-", 250); <br/> mytimer2 M4 = new mytimer2 ("4-", 320 ); </P> <p> m1.mytest (); <br/> m2.mytest (); <br/> m3.mytest (); <br/> m4.mytest (); <br/>}< br/>

2-begin
3-begin
4-begin
1-begin
Thread 1-Time-out, run the daemon thread!
Thread 2-Timeout, run the daemon thread!
3-over
4-over

 

Package CN. vicky; </P> <p> Import Java. io. ioexception; <br/> Import Java. util. timer; </P> <p>/* <br/> * This class provides the main methods for using timer and timertaske, including customizing tasks and adding and exiting tasks, exit the timer. <br/> * because the Status field of timertask is package-level accessible, there is no way in Java. util. the status is obtained outside the package, which causes some inconvenience to programming. <br/> * the status of a task cannot be determined. <br/> */<br/> public class mytimer3 {</P> <p> Public static void main (string [] ARGs) {<br/> timer = new timer (); <br/> mytask mytask1 = new mytask (); <br/> mytask mytask2 = new mytask (); <br/> mytask2.setinfo ("myTask-2"); <br/> timer. schedule (mytask1, 1000,500 0); <br/> timer. scheduleatfixedrate (mytask2, 2000,500 0); <br/> while (true) {<br/> try {<br/> byte [] info = new byte [1024]; <br/> int Len = system. in. read (Info); <br/> string strinfo = new string (Info, 0, Len, "GBK"); // read information from the console <br/> If (strinfo. charat (strinfo. length ()-1) = '') {<br/> strinfo = strinfo. substring (0, strinfo. length ()-2); <br/>}< br/> If (strinfo. startswith ("cancel-1") {<br/> // exit a single task <br/> mytask1.cancel (); <br/> // you should check whether mytask2 has exited. If yes, break should be used. however, you cannot obtain the <br/> // mytask2 status outside the package. Therefore, you cannot determine whether to exit the loop. <br/>} else if (strinfo. startswith ("cancel-2") {<br/> mytask2.cancel (); <br/>} else if (strinfo. startswith ("cancel-all") {<br/> // exit timer <br/> timer. cancel (); <br/> break; <br/>}else {<br/> // only judge mytask1, stealing laziness ^ _ ^ <br/> mytask1.setinfo (strinfo); <br/>}< br/>} catch (ioexception e) {<br/> E. printstacktrace (); <br/>}</P> <p> static class mytask extends Java. util. timertask {<br/> string info = "cmd_^"; </P> <p> @ override <br/> Public void run () {<br/> system. out. println (Info); <br/>}</P> <p> Public String getinfo () {<br/> return Info; <br/>}</P> <p> Public void setinfo (string info) {<br/> this.info = Info; <br/>}</P> <p >}< br/>

Pai_^
MyTask-2
Pai_^
MyTask-2
Oy // The input content will replace the original
Oy

MyTask-2
Oy

MyTask-2
Oy