Java基础之异常Exception(5)---小练习

时间:2023-02-13 12:35:52

ps:案例来源于毕向东老师Java基础教程

练习题目:

老师用电脑上课。
开始思考上课中出现的问题。
比如问题是
电脑蓝屏。
电脑冒烟。
要对问题进行描述,封装成对象。
可是当冒烟发生后,出现讲课进度无法继续。
出现了讲师的问题:课时计划无法完成。

实例代码:

class LanPingException extends Exception {
    LanPingException(String message)
    {
        super(message);
    }
}

class MaoYanException extends Exception {
    MaoYanException(String message)
    {
        super(message);
    }
}


class NoPlanException extends Exception {
    NoPlanException(String msg)
    {
        super(msg);
    }
}

class Computer {
    private int state = 3;
    public void run()throws LanPingException,MaoYanException
    {
        if(state==2)
            throw new LanPingException("蓝屏了");
        if(state==3)
            throw new MaoYanException("冒烟了");

        System.out.println("电脑运行");
    }
    public void reset()
    {
        state = 1;
        System.out.println("电脑重启");

    }
}

class Teacher {
    private String name;
    private Computer cmpt;

    Teacher(String name)
    {
        this.name = name;
        cmpt = new Computer();

    }

    public void prelect()throws NoPlanException
    {
        try
        {
            cmpt.run();         
        }
        catch (LanPingException e)
        {
            cmpt.reset();
        }
        catch (MaoYanException e)
        {

            test();
            throw new NoPlanException("课时无法继续"+e.getMessage());

        }
        System.out.println("讲课");
    }
    public void test()
    {
        System.out.println("练习");
    }

}



class ExceptionTest {
    public static void main(String[] args) 
    {
        Teacher t = new Teacher("毕老师");
        try
        {
            t.prelect();
        }
        catch (NoPlanException e)
        {
            System.out.println(e.toString());
            System.out.println("换老师或者放假");
        }

    }
}