Httpservlet,java Web Backend Service

1, the class of timed execution

Package Com.utils;import java.io.ioexception;import java.text.simpledateformat;import java.util.Date;
Public classMyTimer extends Thread {//interval time: Hours    Private intintervalhours; //error (time required for operation may cause error): minutes    Private intDeviationminute; //Execution Time    PrivateString RunTime;  PublicMyTimer () {//parameter AcquisitionIntervalhours = -; Deviationminute=5; RunTime="19:30"; }         Public voidrun () { while(! This. isinterrupted ()) {//thread does not interrupt execution loop//get current time: hh:mmDate now =NewDate (); SimpleDateFormat DateFormat=NewSimpleDateFormat ("hh:mm"); String hours=Dateformat.format (now); //Time arrives            if(Hours.equals (runTime)) {Dorun (); Try {                    //long-time sleep: Interval time-ErrorThread.Sleep (Intervalhours *3600* +-Deviationminute * -* +); } Catch(interruptedexception e) {e.printstacktrace (); }            }Else{                Try {                    //wait interval: 30sThread.Sleep (30000); System. out. println (hours); } Catch(interruptedexception e) {e.printstacktrace (); }            }        }    }    /** * Processing*/    Private voidDorun () {}}

2,servlet

 Packagecom.utils;ImportJavax.servlet.http.HttpServlet; Public classMyservletextendshttpservlet{/**     *      */    Private Static Final LongSerialversionuid = 1L; PrivateMyTimer MyTimer;  PublicMyservlet () {} Public voidinit () {String str=NULL; if(str = =NULL&& mytimer==NULL) {MyTimer=NewMyTimer ();         Mytimer.start (); }
super.init (); }       Public voiddestory () {if(mytimer!=NULL&&mytimer.isinterrupted ())          {Mytimer.interrupt (); }
　　　　　Super.destroy (); }  }

3,web.xml

    <servlet>        <Servlet-name>Myservlet</Servlet-name>        <Servlet-class>Com.utils.MyServlet</Servlet-class>        <Load-on-startup>9</Load-on-startup
</servlet>

Httpservlet,java Web Backend Service