Compilation Error in overloading.

[AshutoshP Patil]

Hi,
I got this error while compilation if any one of (1) or (2) were uncommented
saying that
reference to method is ambiguous both method method (java.io.IoException) in testing and
method method(java.lang.Integer) in testing match tc.method(null);

But, i am surprised how this java.io.IoException and java.lang.Integer are related .

can anybody please explain me ?


thanks in advance.

public class testing
{

public void method(java.lang.Object o)
{
System.out.println("Object Version");
}

// (1) Starts
/*public void method(java.io.IOException s)
{
System.out.println("IOException Version");
}*/
// (1) Ends

// (2) Starts
/*public void method(java.io.FileNotFoundException s)
{
System.out.println("java.io.FileNotFoundException Version");
}
*/
// (2) Ends

public void method(Integer o)
{
System.out.println("Integer Version");
}

public static void main(String args[])
{
testing tc = new testing();
tc.method(null);
}
}

[Amit Vinod Dali]

A simple cast will solve the problem e.g.

 tc.method((IOException)null);   

For more information on overloading in java Click here

[David Newton]

Please UseCodeTags when posting code or configuration. Unformatted code and configuration is unnecessarily difficult to read.

You can edit your post by using the button.

[AshutoshP Patil]

hi, amit thanks for the reply . My doubt is i have overloaded method() with two argument types one with java.io.IOException and Integer. But, why the compiler thinks that its a ambigous method declaration resulting compilation fail

public class testing
{
public void method(java.io.IOException s) 
{
System.out.println("IOException Version");}

/*public void method(java.io.FileNotFoundException s)
{
System.out.println("java.io.FileNotFoundException Version");
}
*/
public void method(Integer o)
{
System.out.println("Integer Version");
}
public static void main(String args[])
{
new testing().method(null);
}
} 

[David Newton]

Because it's ambiguous: the compiler has no way of knowing which method should be called for a "null" parameter, because either method can take a "null" as input.

[AshutoshP Patil]

thanks david .

[Rob Spoor]

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