overriding and overloading in java

[r035198x]

Hi,
My compiler version is 1.5.0_04.
Note : I am not trying to prove anything wrong. Just trying to resolve my confusion :(

Are you sure? the command is

javac -version

It will show some usage info but will contain the javac version as the first line.
If you look at those errors you should see that your compiler doesn't even support autoboxing

[Nepomuk]

Hm, it works fine with javac 1.5.0_06 under Windows, but with version 1.4.2 under Linux it gives the message

Exception in thread "main" java.lang.Error: Unresolved compilation problem:
     Type mismatch: cannot convert from int to Number

  at Foo.print(Bar.java:5)
  at Bar.main(Bar.java:18)

How very strange!

Greetings,
Nepomuk

[r035198x]

Hm, it works fine with javac 1.5.0_06 under Windows, but with version 1.4.2 under Linux it gives the message

Exception in thread "main" java.lang.Error: Unresolved compilation problem:
     Type mismatch: cannot convert from int to Number

  at Foo.print(Bar.java:5)
  at Bar.main(Bar.java:18)

How very strange!

Greetings,
Nepomuk

Autoboxing was one of the new features in 1.5.

[JosAH]

Autoboxing was one of the new features in 1.5.

If I remember well covariant return types were not allowed in Java 1.4.2 and before;
if I'm right the problem is not autoboxing, it's the covariancy of return types.

kind regards,

Jos

[r035198x]

If I remember well covariant return types were not allowed in Java 1.4.2 and before;
if I'm right the problem is not autoboxing, it's the covariancy of return types.

kind regards,

Jos

You're right. Covariant return types were added in 1.5 together with generics. The problem should be both covariant return types and autoboxing in my example because I'm returning ints where Number and Integer are expected.

[madhoriya22]

Are you sure? the command is

javac -version

It will show some usage info but will contain the javac version as the first line.
If you look at those errors you should see that your compiler doesn't even support autoboxing

I run the command

 
java -version

and it is showing this ..

 
java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_09-b03)
Java HotSpot(TM) Client VM (build 1.5.0_09-b03, mixed mode, sharing)

I know about generics and autoboxing (Although I never used these features). Then how come my compiler is not supporting these feartures.

Sorry I didn't check last posts of u people. Now I get it :)