Generics Query

[Nilesh Raje]

Hi Freinds,

How can this class be completely made to use Generics?

public class WhatDoIDo {
private X x;
private boolean b;
private Object o;

public WhatDoIDo(X x) {
this.x = x;
}

synchronized Object z() {
if (!b) {
o = x.y();
b = true;
}
return o;
}

public interface X {
Object y();
}
}

Thanks

[Punit Singh]

  public class WhatDoIDo<T> { 
	private X x; 
	private boolean b; 
	private Object o; 

	public WhatDoIDo(X x) { 
		this.x = x; 
	} 

	synchronized Object z() { 
		if (!b) { 
			o = x.y(); 
			b = true; 
		} 
		return o; 
	} 

	public interface X { 
		Object y(); 
	} 
	
	public static void main(String[] args) {
		X x=null;
		new WhatDoIDo<String>(x);
	}
} 
  

[EDIT: I did not see interface name is also using X here].

I also do not know the purpose of this program, I think this code should not be generalized legally, as this code has nothing to do with type parameter T, putting T as type parameter is just a waste here and of no use.

[Henry Wong]

This shouldn't compile. The interface T, defined at line 18, is not the same type passed to the generic... hence, line 12 will get a type error.

Henry

[Nilesh Raje]

So what is the right Approach?

[Henry Wong]

Nilesh Raje wrote:So what is the right Approach?

Let's start with... What is the problem that you are trying to solve? Generics is a tool, that is used to solve problems. Taking perfectly running code, and adding generics, just to add generics, doesn't make sense.

Henry

[Nilesh Raje]

Well i was given this code in a test and just asked to make it use generics.

I would appreciate if you could t tell me what is wrong with the code? What do you think the code is actually doing? Now thats making me think good point!