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Java Basics General beginning Java language questions that don't fit in one of the more specific forums. Please specify what version.
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Old March 13th, 2007, 08:28 PM
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Default About object


/*********** CODE *************/
public class Test {
 private int num;

 public Test(int num) { this.num = num; }
 public boolean check(Test obj) {
   return equals(obj);

 public static void main(String[] args) {
   Test m = new Test(2);
   Test n = new Test(2);

/*********** CODE *************/

On the code above java print FALSE, but both value of the objects are equals. I know that those 2 object has different address and that's why they are not equals. My question is how can i make them equals???
In Integer class, if we create 2 different obj with same value, they print statement will print TRUE, How they do that?

I try to create generic class of linked list and i need way to see if the given object as type E is equal to one of the object in my linked list. Since i cannot have an access to obj data, i cannot see that each object carrying same data. but my node class can return obj with type E which is on my list.


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Old March 15th, 2007, 12:08 PM
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What you're doing here is checking the equality of the Objects themselves. This means that, because you create both m and n with it's own new statement then m and n will be different according to what the equals method checks for.

In order to have this working the way you want it to, you need to create your own equals method for your class to override Object's equals method.

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