定时器的用法是java核心基础之一，很多特殊功能都需要用到定时器，下面一起来看看定时器是如何编写的吧。
示例：一个具备周期性定时(毫秒级);单时刻定时(秒级);多时刻定时(秒级)。后两个时间的设置必须符合“yyyy-MM-dd HH:mm:ss”、“yyyy-MM-dd ”、“HH:mm:ss”、“HH:mm”、“yyyy-MM-dd HH”、“yyyy-MM-dd HH:mm”格式的定时器
Java代码
//TimerTask代码
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
public abstract class TimerTask implements Runnable
{
private long period = -1;
private String time;
private List < String > timeList;
private boolean isCancel = false;
private boolean isFormart = false;
public long getPeriod()
{
return period;
}
public void setPeriod(long period)
{
this.period = period;
}
public void setTime(String time)
{
this.time = time;
}
public String getTime()
{
return time;
}
public List < String > getTimeList()
{
return timeList;
}
public void setTimeList(List < String > timeList)
{
this.timeList = timeList;
}
public void cancel()
{
this.isCancel = true;
}
public boolean isCancel()
{
return isCancel;
}
public abstract void execute();
public void run()
{
//格式化传入的日期或日期时间或时间参数
if (!this.isFormart)
{
this.fomart();
}
//确保指定的运行点在一秒钟内只运行一次
boolean isRun = false;
//确保多个运行点中，每个运行点在一秒钟内只运行一次
int flag[] = null;
try
{
flag = new int[this.timeList.size()];
}
catch (Exception e)
{}
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
//当没有被取消时
while (!isCancel)
{
String dt = sdf.format(new Date());
if (this.period > 0)
{
try
{
Thread.sleep(this.period);
}
catch (Exception e)
{}
this.execute();
}
else if (this.time != null)
{
if (this.time.indexOf("-") > 0)
{
if (this.time.equals(dt) && !isRun)
{
isRun = true;
this.execute();
}
}
else
{
if (this.time.equals(dt.substring(11)) && !isRun)
{
isRun = true;
this.execute();
}
}
}
else if (this.timeList != null)
{
int loopIndex = 0;
for (String dateTime: this.timeList)
{
if (dateTime.indexOf("-") > 0)
{
if (dateTime.equals(dt) && flag[loopIndex] == 0)
{
this.execute();
flag[loopIndex] = 1;
}
}
else
{
if (dateTime.equals(dt.substring(11)) && flag[loopIndex] == 0)
{
this.execute();
flag[loopIndex] = 1;
}
}
++loopIndex;
}
}
}
}
private void fomart()
{
if (!this.isFormart)
{
if (this.time != null)
{
this.time = this.format(this.time);
}
if (this.timeList != null)
{
for (int i = 0; i < this.timeList.size(); i++)
{
String dateTime = this.timeList.get(i);
if (dateTime != null)
{
this.timeList.set(i, format(dateTime));
}
}
}
}
else
{
this.isFormart = true;
}
}
private String format(String datetime)
{
if (datetime != null)
{
// 是否含有减号
boolean hasSubtrSign = datetime.contains("-");
// 是否含有冒号
boolean hasColonSign = datetime.contains(":");
// 12-23 12:33
if (hasSubtrSign == true && hasColonSign == true)
{
datetime = DateUtil.formatToEnglish(datetime);
}
else if (hasSubtrSign && hasColonSign == false)
{
datetime = DateUtil.formatToEnglish(datetime);
}
else if (hasSubtrSign == false && hasColonSign)
{
datetime = DateUtil.formatToEnglish(datetime)
.substring(11);
}
}
return datetime;
}
}
///////////////////////////////////////////////////////////////////
//Timer代码
import java.util.ArrayList;
public class Timer extends Thread
{
private boolean isStart = false;
private boolean isCannel = false;
ArrayList < TimerTaskBean > tasks = new ArrayList < TimerTaskBean > ();
public Timer()
{}
public void cancel()
{
this.isCannel = true;
}
public boolean isCannel()
{
return isCannel;
}
public void schedule(TimerTask task, long period)
{
task.setPeriod(period);
//添加任务
this.addTask(task);
}
public void schedule(TimerTask task, long delay, long period)
{
try
{
Thread.sleep(delay);
}
catch (Exception e)
{}
task.setPeriod(period);
//添加任务
this.addTask(task);
}
public void schedule(TimerTask task, String time)
{
task.setTime(time);
//添加任务
this.addTask(task);
}
public void schedule(TimerTask task, long delay, String time)
{
try
{
Thread.sleep(delay);
}
catch (Exception e)
{}
task.setTime(time);
//添加任务
this.addTask(task);
}
public void schedule(TimerTask task, java.util.List < String > timeList)
{
task.setTimeList(timeList);
//添加任务
this.addTask(task);
}
public void schedule(TimerTask task, long delay, java.util.List < String > timeList)
{
try
{
Thread.sleep(delay);
}
catch (Exception e)
{}
task.setTimeList(timeList);
//添加任务
this.addTask(task);
}
//添加任务
private void addTask(TimerTask task)
{
boolean isExist = false;
for (TimerTaskBean ttBean: this.tasks)
{
if (task.equals(ttBean.getTask()))
{
isExist = true;
break;
}
else
{
isExist = false;
}
}
if (!isExist)
{
tasks.add(new TimerTaskBean(task, false));
}
//判断定时器线程是否启动
if (!this.isStart)
{
this.start();
this.isStart = true;
}
}
public void run()
{
// 是否取消所有任务的定时功能
while (!this.isCannel)
{
for (int i = 0; i < tasks.size(); i++)
{
TimerTaskBean ttBean = tasks.get(i);
//判断是否开始运行
if (ttBean != null && !ttBean.isRun())
{
ttBean.setRun(true);
new Thread(ttBean.getTask())
.start();
}
}
}
//当取消定时器时，取消所有任务
if (this.isCannel)
{
for (TimerTaskBean ttBean: tasks)
{
ttBean.getTask()
.cancel();
}
}
}
class TimerTaskBean
{
public TimerTaskBean()
{}
public TimerTaskBean(TimerTask task, boolean isRun)
{
this.task = task;
this.isRun = isRun;
}
private boolean isRun = false;
private TimerTask task = null;
public boolean isRun()
{
return isRun;
}
public void setRun(boolean isRun)
{
this.isRun = isRun;
}
public TimerTask getTask()
{
return task;
}
public void setTask(TimerTask task)
{
this.task = task;
}
}
}
////////////////////////////////////////////////////////////////
//TimerTest代码
import java.util.ArrayList;
public class TimerTest
{
public static void main(String[] args)
{
Timer t = new Timer();
T1 t1 = new T1();
T2 t2 = new T2();
t.schedule(t1, 1000);
ArrayList < String > list = new ArrayList < String > ();
list.add("11:44:30");
list.add("11:44:31");
list.add("11:44:32");
list.add("11:44:33");
list.add("11:44:34");
list.add("11:44:35");
list.add("11:44:36");
list.add("11:44:37");
t.schedule(t1, list);
try
{
Thread.sleep(1000 * 4);
}
catch (Exception e)
{}
t1.cancel(); //取消任务1,任务2线程停止
t.schedule(t2, 1000);
t.schedule(t2, list);
try
{
Thread.sleep(1000 * 4);
}
catch (Exception e)
{}
t2.cancel(); //取消任务2,任务2线程停止
try
{
Thread.sleep(1000 * 4);
}
catch (Exception e)
{}
t.cancel(); //取消定时器,定时器线程停止
}
}
class T1 extends TimerTask
{
public T1()
{}
public void execute()
{
System.out.println(11111111);
}
}
class T2 extends TimerTask
{
public T2()
{}
public void execute()
{
System.out.println(22222222);
}
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