Timer 的学习

Timer 实例化多个对象就会启动多个线程

TimerTask 中 捕获异常为基类Exception，那么出现异常后就继续执行.及时报错

TimerTask中未捕获异常或者捕获异常与程序抛出异常不一致，都会导致当前线程停止。

TaskTEST1.java ：不捕获异常
package TaskTestPackage;
import java.util.TimerTask;
public class TaskTEST1  extends TimerTask{
       boolean bool=true;
       int i=;
       @Override
       public void run() throws ArrayIndexOutOfBoundsException{
              i=i+;
              if (i>) {
                     throw new RuntimeException();
              }else {
                     System.out.println(i);
              }
       }
}
TaskTEST2.java
package TaskTestPackage;
import java.util.TimerTask;
public class TaskTEST2  extends TimerTask{
       int a=;
       @Override
       public void run() {
              // TODO Auto-generated method stub
              a=a-;
              System.out.println(a);
       }
}
ETL.java
package TaskTestPackage;
import java.util.Date;
import java.util.Timer;
public class ETL {
        public static void main(String[] args) {
             Timer timer=new Timer();
             timer.schedule(new TaskTEST1(),  new Date(), );
             Timer timer1=new Timer();
             timer1.schedule(new TaskTEST2(),  new Date(), );
        }
}
执行结果：

修改TaskTEST1.java：捕获异常为Exception 基类
package TaskTestPackage;
import java.util.TimerTask;
public class TaskTEST1  extends TimerTask{
       boolean bool=true;
       int i=;
       @Override
       public void run() throws ArrayIndexOutOfBoundsException{
              try {
                     i=i+;
                     if (i>) {
                           throw new RuntimeException();
                     }else {
                           System.out.println(i);
                     }
              }catch(Exception ex){
                     System.out.println(ex);
              }
       }
}
执行结果如下

修改TaskTEST1.java：捕获异常与抛出异常不一致
package TaskTestPackage;
import java.util.TimerTask;
public class TaskTEST1  extends TimerTask{
       boolean bool=true;
       int i=;
       @Override
       public void run() throws ArrayIndexOutOfBoundsException{
              try {
                     i=i+;
                     if (i>) {
                           throw new RuntimeException();
                     }else {
                           System.out.println(i);
                     }
              }catch(ArrayIndexOutOfBoundsException ex){
                     System.out.println(ex);
              }
       }
}
执行结果：