/*
毕老师用电脑上课。
问题领域中涉及两个对象。
毕老师，电脑。
分析其中的问题。
比如电脑蓝屏啦。冒烟啦。
*/
class LanPingException extends Exception
{
LanPingException(String msg)
{
super(msg);
}
}
class MaoYanException extends Exception
{
MaoYanException(String msg)
{
super(msg);
}
}
class NoPlanException extends Exception
{
NoPlanException(String msg)
{
super(msg);
}
}
class Computer
{
private int state = 2;
public void run()throws LanPingException,MaoYanException
{
if(state==1)
throw new LanPingException("电脑蓝屏啦！！");
if(state==2)
throw new MaoYanException("电脑冒烟啦！！");
System.out.println("电脑运行");
}
public void reset()
{
state = 0;
System.out.println("电脑重启");
}
}
Lan异常
Computer类run方法告诉问题
Teacher类prelect预先给出处理方法（catch）
Mao异常
Teacher prelect中不能处理的异常，继续抛出，throw。Prelect标识
在exceptiontest catch 被抛出的异常，进行处理。
class Teacher
{
private String name;
private Computer comp;
Teacher(String name)
{
this.name = name;
comp = new Computer();
}
public void prelect()throws NoPlanException
{
try
{
comp.run();
System.out.println(name+"讲课");
}
catch (LanPingException e)
{
System.out.println(e.toString());
comp.reset();
prelect();
}
catch (MaoYanException e)
{
System.out.println(e.toString());
test();
//可以对电脑进行维修。
// throw e;
throw new NoPlanException("课时进度无法完成，原因："+e.getMessage());
}
}
public void test()
{
System.out.println("大家练习");
}
}
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("换人");
}
}
}
/*
class NoAddException extends Exception
{}
void addData(Data d)throws NoAddException
{
连接数据库
try
{
添加数据。出现异常 SQLException();
}
catch(SQLException e)
{
//处理代码。
throw new NoAddException();
}
fianlly
{
关闭数据库。
}
}
*/