需要修复我的Java计时器代码吗

任务-在一天中的指定时间打开和关闭灯泡。我需要知道如何根据下面给出的信息修复我的代码。我还需要知道我是否正确使用了timer类，也就是说，我的代码设计是否正确？代码可能会工作，但可能是糟糕的设计，这将在以后导致问题。我不想那样

输出是（这不是我真正想要的输出：（）-

期望输出-

This is the main program
Current time is - xxx
Future time is - xxx+5sec
Future time is - xxx+10sec
Bulb B1 is ON  //first on
Bulb B1 is OFF //then off
Main program ends//This should always be in the end.

我如何修复下面的代码以获得我想要的

灯泡

等级

class Bulb {

private boolean state = false;//On or off
private String name;

Bulb(String name){

    this.name = name;

}

public void setState(boolean state){

    this.state = state;
    if(this.state == true){

        System.out.println("Bulb " + name + " is ON");

    }else{

        System.out.println("Bulb " + name + " is OFF");

    }

}


public boolean getState(){
    return this.state;

}


}

BulbJob

类，它是一个

TimerTask

import java.util.*;

class BulbJob extends TimerTask{

private Bulb bulbToHandle;
private boolean setBulbStateEqualTo;

BulbJob(Bulb toHandle){

    this.bulbToHandle = toHandle;

}


//NOTE: Must be called before run(), otherwise default value is used
public void setBulbStateEqualTo(boolean setBulbStateEqualTo){

    this.setBulbStateEqualTo = setBulbStateEqualTo;

}


//NOTE: call run() only before calling above method
public void run(){

    this.bulbToHandle.setState(setBulbStateEqualTo);//Set on or off

}

}

BulbScheduler

class-此计划在灯泡打开或关闭时进行

import java.util.*;

@SuppressWarnings( "deprecation" )
class BulbScheduler {

public static void main(String args[]) throws InterruptedException{

    System.out.println("This is the main program");

    Timer time = new Timer();
    Bulb b1 = new Bulb("B1");
    BulbJob bj = new BulbJob(b1);

    bj.setBulbStateEqualTo(true);//Task - Turn bulb on at time = afterCurrent

    Date current = new Date();//Get current time and execute job ten seconds after this time
    Date afterCurrent = (Date) current.clone();

    System.out.println("Current time is - " + current);

    int currentSecs = current.getSeconds();
    int offset = 5;//number of seconds

    afterCurrent.setSeconds(currentSecs + offset);
    System.out.println("Future time is - " + afterCurrent);

    time.schedule(bj, afterCurrent);//Schedule job "bj" at time = afterCurrent

    //Now turn the bulb off at new time = newest afterTime
    afterCurrent.setSeconds(currentSecs + 2 * offset);
    System.out.println("Future time is - " + afterCurrent);

    bj.setBulbStateEqualTo(false);//Task - Now turn the bulb off at time = afterCurrent

    System.out.println("Main program ends");

}

}

本节：

time.schedule(bj, afterCurrent);//Schedule job "bj" at time = afterCurrent

//Now turn the bulb off at new time = newest afterTime
afterCurrent.setSeconds(currentSecs + 2 * offset);

仅计划一项任务。如果需要计划两次，请明确执行以下操作：

time.schedule(bj, afterCurrent);//Schedule job "bj" at time = afterCurrent

//Now turn the bulb off at new time = newest afterTime
afterCurrent.setSeconds(currentSecs + 2 * offset);
time.schedule(bj, afterCurrent);//Schedule job "bj" at time = afterCurrent

此外，这一行：

bj.setBulbStateEqualTo(false);

---

在主线程中执行，因此它将在两个任务之前执行。您应该计划该语句在两个任务之间运行。

代码已修复，但此版本最终无法退出main-

import java.util.*;

@SuppressWarnings( "deprecation" )
class BulbScheduler {

public static void main(String args[]) throws InterruptedException{

    System.out.println("This is the main program");

    Timer timeOn = new Timer();
    Timer timeOff = new Timer();
    Bulb b1 = new Bulb("B1");
    BulbJob bjOn = new BulbJob(b1);
    BulbJob bjOff = new BulbJob(b1);

    bjOn.setBulbStateEqualTo(true);//Task - Turn bulb on 
    bjOff.setBulbStateEqualTo(false);//Task - Then turn the bulb off later

    Date current = new Date();//Get current time and execute job ten seconds after this time
    Date afterCurrent = (Date) current.clone();

    System.out.println("Current time is - " + current);

    int currentSecs = current.getSeconds();
    int offset = 3;//number of seconds

    afterCurrent.setSeconds(currentSecs + offset);
    System.out.println("Future time is - " + afterCurrent);

    timeOn.schedule(bjOn, afterCurrent);//Schedule job "bj" at time = afterCurrent

    //Now turn the bulb off at new time = latest afterCurrent
    afterCurrent.setSeconds(currentSecs + 2 * offset);
    System.out.println("Future time is - " + afterCurrent);

    timeOff.schedule(bjOff, afterCurrent);

    System.out.println("Main program ends");

}

}

---

您没有正确设置时间。需要使用GreogarianCalendar

使用java.util.Date，但不能使用其setSeconds读取Javadoc，这很好，会有很大帮助。public void setSeconds（int seconds）

不推荐使用。从JDK版本1.1开始，替换为Calendar.set（Calendar.SECOND，int seconds）。 将此日期的秒数设置为指定值。修改此日期对象，使其表示指定秒数内的时间点，年、月、日期、小时和分钟与以前相同，在本地时区中进行解释

您需要使用java.util.GregorianCalendar#add（Calendar.SECOND，howManySeconds）

然后使用getDate（）获取日期对象并将其发送给计时器

---

在日期上调用setSecond不会更改其他字段。请参阅Calendar.add and roll的java文档，并查看inro类中的规则。

还可以使用计时器对象的计划（TimerTask任务，长延迟） 计划在指定延迟（毫秒）后执行指定的任务。 修改代码-

import java.util.*;

class BulbScheduler {

    private static java.text.SimpleDateFormat sdf1 = new java.text.SimpleDateFormat ("yy MM dd HH mm ss");

//helper    
static String formatDate(Date d){
        return sdf1.format(d);
    }

    public static void main(String args[]) throws InterruptedException{
        System.out.println("This is the main method");
        java.util.GregorianCalendar cal = new java.util.GregorianCalendar();

        Bulb b1 = new Bulb("bulb 1", false);
        Bulb b2 = new Bulb("bulb 2", false);

        System.out.println("Time now " + formatDate(cal.getTime()));

        Timer timer = new Timer("bulbs");
        BulbJob b1On = new BulbJob(b1, true);
        BulbJob b1Off = new BulbJob(b1, false);
        BulbJob b2On = new BulbJob(b2, true);
        BulbJob b2Off = new BulbJob(b2, false);
        timer.schedule(b1On, 3 * 1000);//after 3 seconds
        timer.schedule(b2On, 7 * 1000);//after 4 seconds
        timer.schedule(b1Off, 6 * 1000);//after 6 seconds; before b2 on

        b1On = new BulbJob(b1, true);
        timer.schedule(b1On, 9 * 1000);


        //if you want main to wait need to add code here to make it wait,
        // but even if does the JVM wont exit. Its just a method. The JVM exits when all non daemon threads are done
        // or System.exit is called

        System.out.println("This is the main method ending; but other threads might be running ...");
        //main thread JVM waits for all other non dameons to end

    }

}

改变了BulbJob

导入java.util.*

类BulbJob扩展了TimerTask{

private Bulb bulbToHandle;
private boolean bulbNewState;//dont start propert names with set

//why a seperate property when we need to set the new state everytime and cannot reuse jobs?
BulbJob(Bulb toHandle, boolean newState){
    this.bulbToHandle = toHandle;
    bulbNewState= newState;
}

public void run(){
    this.bulbToHandle.setState(bulbNewState);//Set on or off
}

}

班级灯泡。。。 公共无效设置状态（布尔状态）{ this.state=状态； System.out.println（“bull”+name+“是”+（状态？“开”）：“关”）+“在”+BulbScheduler.formatDate（new java.util.Date（））；//如果还可以的话

---

}

+1选择

TimerTask

而不是普通的

线程
sleep（）
@asgs-如何使“主程序结束”只在执行完所有操作后才出现？由于主线程不依赖于您的作业，恐怕您需要重新设计，以便使用
线程
的
加入（）
方法等待TimerTask完成。@asgs-那么，BulbJob扩展了线程？？？但是，我将丢失所有TimerTask功能。如何修复此问题（@asgs-还有，这就是我想做的-在currentTime+5秒打开灯泡。然后，在currentTime+10秒关闭同一个灯泡。我是否必须创建新的灯泡或计时器来关闭它？同样，这也是我想做的-在currentTime+5秒打开灯泡。然后，在currentTime+10秒关闭同一个灯泡。我是否必须创建新的灯泡bJob或Timer关闭它？创建3个任务：turnBulbOn、turnBulbOff、ExitProgram，完成这些任务并一个接一个地安排它们。你只需要一个计时器。好了。使用自定义消息作为单独的
TimerTask
退出程序是最好的选择。@assylias-我该如何完成ExitProgram任务？我还需要做其他事情吗s按照计划工作。我添加了修改后的代码作为我的答案。只是部分正确。设置秒不是办法。尝试从2:59:59开始的日期时间不会到3:00:00。查看其他答案，使用Calendar.roll查看java.util.date#SetSecondy的api javadoc您正在主线程中打印
主程序结束
，它将立即执行如果你想让它延迟，你需要用它做一个任务，并在关掉灯泡后运行。@assylias-好的。我可以做EnProgram任务。但是，我只能在bjOff之后运行它。因此，我必须跟踪所有的计时，这非常不方便。不幸的是，没有join（）TimerTask的方法，即仅在task2完成后完成task1。您也可以使用阻止机制，例如倒计时闩锁。这是一个错误的实现。设置秒不是最好的方法。请尝试将日期时间从2:59:59改为3:00:00。若要查看其他答案，请使用Calendar.roll
private Bulb bulbToHandle;
private boolean bulbNewState;//dont start propert names with set

//why a seperate property when we need to set the new state everytime and cannot reuse jobs?
BulbJob(Bulb toHandle, boolean newState){
    this.bulbToHandle = toHandle;
    bulbNewState= newState;
}

public void run(){
    this.bulbToHandle.setState(bulbNewState);//Set on or off
}