for each prob

[kusumathatavarthi]

Hi i do have problem with this code can any body help me out regarding


public class Main implements Comparable {

public String drink;

public int compareTo(Object o) {
return 0;
}

public static void main(String[] a) {


Main mn1 = new Main();
Main mn2 = new Main();
mn1.drink = "tea";
mn2.drink = "cafe";
TreeSet tree = new TreeSet();
tree.add(mn1);
tree.add(mn2);
////////////////////error block/////////
for(Main m : tree){ types incompatible
//////////////////eb////////////////////
System.out.print(m.drink);
}

}
}

[Eranga]

For loop definition is wrong. What you really want to do. Give more details about your application.

[kusumathatavarthi]

I am just executing the SCJP Qs

here i want to iterate each set and want to print the name of each drink.

[DonCash]

I think you may need to change this to:

for(String m : tree){
}

I haven't tested it though. Let me know what happens.

[Eranga]

I don't think so. Again there is incompatible variables found. Isn't it?

[DonCash]

I don't think so. Again there is incompatible variables found. Isn't it?

Like I said I didnt actually test it but your right. After looking at it further this will actually still cause an error.

'Cannot convert from element type Object to main'

[kusumathatavarthi]

I've one more q to get clarified,

Diff btwn

Integer i = 0;
int i=0;

when we do ++i ,i++// in both cases result is diff

why is that so

[DonCash]

++i is pre increment

and

i++ is post increment.

Take a look at this:

Incremental Java