Getting Started with Java-timed scheduling

Getting Started with Java-timed scheduling Timer class

The Timer class is a threading facility that can be used to schedule a task to be executed once or periodically after a certain time or a certain period of time, which is used in conjunction with Timetask.

Each timer object corresponds to a thread, so the task performed by the timer should be completed quickly, and no one may delay the execution of subsequent tasks.

Serial number	Method	Type	Describe
1	Timer ()	Structure	Create a timer, and start the timer
2	Cancle ()	Ordinary	Terminates the timer and discards all scheduled tasks
3	Purge ()	Ordinary	Remove a canceled task, which is typically used to free up memory space
4	Schedule (TimerTask task,date time)	Ordinary	Schedule a task to execute at a specified time
5	Schedule (TimerTask task,date Firsttime,long period)	Ordinary	Schedule a task to execute at a specified time and then repeat it at a fixed frequency
6	Schedule (TimerTask task,long Delay,long period)	Ordinary	Schedule a task to be specified after a period of time and repeat at a fixed frequency
7	Scheduleatfixedrate (TimerTask task,date Firsttime,long period)	Ordinary	Schedule a task to execute at a specified time and then repeat at an approximate fixed frequency
8	Scheduleatfixedrate (TimerTask task,long Delay,long period)	Ordinary	Schedule a task to execute after a period of time and then repeat at an approximate fixed frequency

TimerTask class

is an abstract class that requires the creation of an abstract method in which subclasses are implemented.

Serial number	Method	Type	Describe
1	Cancle ()	Ordinary	Used to terminate this task, if the task is executed only once and has not been executed, it will never be executed, and if it is executing, it will no longer execute and will not be executed again if the task is repeatedly executed.
2	Run ()	Ordinary	The specific action to be performed by the task, the method that is introduced in the interface runnable, the subclass needs to inherit this method
3	Scheduled ExecutionTime ()	Ordinary	Returns the most recent time to perform the task, typically called in the Run () method, to determine whether there is currently enough time to perform the task

Example

The current time of the scheduled print system.

/* Summary, you need to create a Task object, set up a Timer object * Task class inheritance with an abstract class TimerTask, this abstract class to implement the Run method. */package sep27;import java.util.*;import java.text.*;p ublic class MyTask {public static void main (string[] args) {Timer T =new Timer (); Texttask testtask=new texttask (); T.schedule (Testtask, 1000, 2000);}} Class Texttask extends Timertask{public void run () {SimpleDateFormat sdf1=null;sdf1=new SimpleDateFormat ("yyyy year MM DD Day HH:mm:ss. SSS "); System.out.println ("Current time is:" +sdf1.format (New Date ()));}}

Results:

Current time: September 27, 2016 16:09:14.493 current time is: September 27, 2016 16:09:16.231 current time is: September 27, 2016 16:09:18.231 current time is: September 27, 2016 16:09:20.236 Current time: September 27, 2016 16:09:22.238 current time is: September 27, 2016 16:09:24.242 current time is: September 27, 2016 16:09:26.245 Current time: September 27, 2016 16:09:28.247

　　

Getting Started with Java-timed scheduling