[求助]再次求助

import java.io.*;
class MyException extends Exception
{
MyException()
{
super();
}
MyException(String s)
{
super(s);
System.out.println("the Exception with ABCD");
}
}

public class exception2
{
public static void main(String args[])throws IOException
{
while(true)
{
try
{
fn();
}
catch(RuntimeException e)
{
try
{
throw e.getCause();//这个方法不对么
}
catch(IOException s)
{
System.out.println("please again");
}
catch(MyException m)
{
break;
}

}
}
}
static void fn()
{
try
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("putout u String");
String temp=br.readLine();
if(temp.equals("ABCD")==false)
{
throw new IOException();
}
else if(temp.equals("ABCD")==true)
{
throw new MyException("ABCD");
}
}catch(Exception e)//把他包装成runtime的异常
{
throw new RuntimeException(e);
}

}
}

怎么解决,让异常正确识别其类型????

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用instanceof
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try
{
if(e instanceof IOException)
throw new IOException();//这个方法不对么
else throw new MyException();
}
不行啊
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2楼谢谢了
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呵呵,我的方法不管用么?
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说错了
3楼.............
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汗,还以为我的方法不行呢

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我们刚好上到这儿
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