Ranch roundup game question

[Jas Oberai]

Hi Friends,
I got this question:

Can you pass a short into a method call when an int is expected?
Answer:Yes
Since a short will definately fit into an int,the short is implictly promoted.No cast needed.

But,I answered "No",as I read this in the JLS specification:

Method Invocation Conversions do not include implicit narrowing of integer constants as in Assignment conversions.

The also explained that it was done so as not to confuse regarding overloading.So,why the answer was "Yes",please explain this to me guys!!!

[James Carman]

You're not "narrowing" when you go from short to int. It would be narrowing when you go from int to short.

[Karthikeyan Varadarajan]

You can send int while the funtion expects int. but the vice versa is true.

while coming to overloading ,

the compiler try to match the argument type and if it is not find a correct method , then try to widen the values and match (short to int or int to long).

<code>
public class OverLoadTest {

public static void main(String[] args) {

OverLoadTest test = new OverLoadTest();
short ding = 5;
test.checkOverLoad(ding);

}


/* public void checkOverLoad (int one)
{
System.out.println("CheckOverLoad for int called");
}*/

/* public void checkOverLoad (short two)
{
System.out.println("CheckOverLoad for Short called");
}*/

public void checkOverLoad (long three)
{
System.out.println("CheckOverLoad for Long called");
}
}

</code>

[Jas Oberai]

Thanks James and BlackFire,
So,that only happens for narrowing and not widening..got it!!!
thanks

[Raghu Shree]

Thanks James and blackfire,
Nice Example. I got the point.
[ May 06, 2005: Message edited by: Raghu Shree ]

[Parameswaran Thangavel]

hi james

i didn't understand what the jls saying Method Invocation Conversions do not include implicit narrowing of integer constants as in Assignment conversions.

i learnt that in assignment coversion. we can assign int to short i.e narrowing on explicitly casting.
i.e Short s=(Short)5;

is the jls saying the above conversion is not allowed during the method invocation.

[James Carman]

It means that you can do this...

  
byte b = 123;

But, you can't do this...

  
public class Narrower
{
  public static void main( String[] args )
  {
    someMethod( 123 );
  }
 
  private static void someMethod( byte b ) {}
}