Ambiguity in overloaded methods

[dennis zined]

Hi all.
I'm getting an ambigous compile-time error on line 5 of the code below. The method being invoked is supposedly an inherited method from Base1. Class Derived1 contains an overloaded version of this method. Compiling the code results in an ambiguous error. That's all good but what I dont understand is that class Temp also contains the same overloaded methods and I can invoke the int version without any ambiguity.
I would appreciate some enlightenment from anyone here. Thanks.
Kung Hei Fat Choi to Chinese Ranchers!

1public class Temp {
2    public static void main(String[] args) throws Exception{
3
4        Derived1 d = new Derived1();
5        System.out.println(d.getVal(10, 7));  // why the hell is this ambigous
6                                                // compile time error?
7
8        Temp t = new Temp();
9        System.out.println(t.getVal(10, 7));    // this is ok, executes int version of
10                                                // of the overloaded methods.
11    }
12    public int getVal(int a, int b){
13            return a - b;
14    }
15    public long getVal(long a, long b){
16            return a + b;
17    }
18}
19class Base1{
20    public int getVal(int a, int b){
21        return a - b;
22}}
23class Derived1 extends Base1{
24    public long getVal(long a, long b){
25        return a + b;
26}}

[Alton Hernandez]

May I know the version of your compiler? I believe it has something to do with the way the compiler handles the 'most specific method'. There had been some changes in the JLS regarding this issue and your compiler may not be up-to-date.
My compiler's version is 1.4.2 and compiles fine. And if I run it, the output is 3 3.

[dennis zined]

Hi Alton.
Couple of things:
- I have java version 1.4.2_03 and its the only one on my machine.
- I always use eclipse to compile and run my code. Version of eclipse is 2.1.2. I configured eclipse to use the installed jdk 1.4.2_03.
Steps I took after reading your post:
- Compiled and ran the code outside eclipse (used notepd). Compiler is still the alredy installed jdk 1.4.2_03
- Code compiled and ran fine!
So I'm arriving at a conclusion that this might be an IDE problem? But the IDE is using jdk 1.4.2_03?
Thanks.