java使用getter和setter方法并返回0 [英] java using getter and setter methods and returning 0

问题描述

我在2个单独的类中创建了2个计时器。一个计时器递增int计数器。另一个使用get方法并打印出int计数器的值。

I have created 2 timers in 2 separate classes. One timer increments int counter. and the other uses a get method and prints out the value of int counter.

问题是如果我使用 private int counter $，第二个计时器仅打印出0、0、0等。 b $ b而如果我要使用私有静态计数器，它会打印出1,2,3,4,5等，这正是我想要的。但是我宁愿不使用 static ，因为我被告知香港专业教育学院的不良做法。

The problem is the second timer only prints out 0, 0, 0 etc if i use private int counter whereas if i were to use private static counter it prints out 1,2,3,4,5 etc which is what i want. But i would rather not use static because ive been told its bad practice.

这是我的主要课程：

import java.util.Timer;
public class Gettest {

public static void main(String[] args) {

    classB b = new classB();
    classC c = new classC();

    timer = new Timer();
    timer.schedule(b, 0, 2000);
    Timer timer2 = new Timer();
    timer2.schedule(c, 0, 2000); }}

具有timer1的B类

class B with timer1

import java.util.TimerTask;
public class classB extends TimerTask  {

private int counter = 0;

public int getint()
{ return counter;}

public void setint(int Counter)
{ this.counter = Counter;}

 public void run()
 { counter++;
   this.setint(counter);}}

带有计时器2的C类

import java.util.TimerTask;
public class classC extends TimerTask 
{
classB b = new classB();

public void run(){
System.out.println(b.getint());}}

我该如何解决，以便它可以使用 private int counter; 吗？

How could i fix so i it works using private int counter;?

推荐答案

您有两个完全唯一/独立的ClassB实例，一个实例使用Timer运行，另一个实例显示。显示的一个永远不会更改，因为它没有在计时器中运行，因此它将始终显示初始默认值0。

You've got two completely unique/separate ClassB instances, one you run with a Timer, the other you display. The displayed one never changes since it's not run in a Timer, and so it will always display the initial default value of 0.

如果更改它，则只有一个实例：

If you change it so you have only one instance:

import java.util.Timer;
import java.util.TimerTask;

public class Gettest {
    private static Timer timer;

    public static void main(String[] args) {
        ClassB b = new ClassB();
        ClassC c = new ClassC(b); // pass the B instance "b" into C
        timer = new Timer();
        timer.schedule(b, 0, 2000);
        Timer timer2 = new Timer();
        timer2.schedule(c, 0, 2000);
    }
}

class ClassB extends TimerTask {
    private int counter = 0;

    public int getint() {
        return counter;
    }

    public void setint(int Counter) {
        this.counter = Counter;
    }

    public void run() {
        counter++;
        this.setint(counter);
    }
}

class ClassC extends TimerTask {
    ClassB b;

    // add a constructor to allow passage of B into our class
    public ClassC(ClassB b) {
        this.b = b;  // set our field
    }

    public void run() {
        System.out.println(b.getint());
    }
}

代码将起作用。

作为辅助建议，请再次进行代码格式化，并努力使其符合Java标准。例如，请参见上面的代码。

As a side recommendation, again, please work on your code formatting, and strive so that it conforms to Java standards. For example, please see my code above.

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