1. 
   
2. <P>public class SuperClass </P>
   
3. <P>{
   
4. 
   
5. 02 public void start() throws IOException</P>
   
6. <P>{
   
7. 
   
8. 03 throw new IOException("Not able to open file");
   
9. 
   
10. 04 }
    
11. 
    
12. 05 }
    
13. 
    
14. 06
    
15. 
    
16. 07 public class SubClass extends SuperClass</P>
    
17. <P>{
    
18. 
    
19. 08 public void start() throws Exception</P>
    
20. <P>{</P>
    
21. <P>
    
22. 09 throw new Exception("Not able to start");
    
23. 
    
24. 10 }
    
25. 
    
26. 11 }
    
27. </P>

复制代码

请问这段代码有什么错误？
求详解

你的上面父类抛的异常是IOException  而子类抛得异常是Exception 这样不行。。要么在上面加Exception
import java.io.IOException;


public class SuperClass
{

public void start() throws IOException,Exception
{

        throw new IOException("Not able to open file");

}

}



class SubClass extends SuperClass
{

         public void start() throws Exception
         {

                 throw new IOException("Not able to start");

         }

}


要么如下代码  都抛IOException

import java.io.IOException;


public class SuperClass
{

public void start() throws IOException
{

        throw new IOException("Not able to open file");

}

}



class SubClass extends SuperClass
{

         public void start() throws IOException
         {

                 throw new IOException("Not able to start");

         }

}

子类中就尽量不要抛出什么异常