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a doubt in equals() method

 
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hello friends,
thanx very much for your previous responses for my doubt in exception hadling.plz clear me of this doubt about equals() method.

question:

class a
{
a(int x)
{
System.out.println(x);
}
}

class b
{
public static void main(String args[])
{
a ob1=new a(100);
a ob2=new a(100);

System.out.println(ob1.equals(ob2));
}
}


the output of this is false,even though both ob1 and ob2 are objects of class a and the value passed to the constructor is also same.i thought that .equals() method checks the contents of the object and returns a boolean value.
please clear me of this doubt as how .equal() works,
regards,
raja
 
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The default equals method (supplied by java.lang.Object) actually uses ==

If you want to use equals for your own classes, you have to override public boolean equals(Object o), and make it do something sensible for your type.

this might be interesting
 
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equals() on Object(Except for String & Wrapper Classes) uses == operator.

for example
Object o=new Object();
Object o1=o;
if(o1.equals(o)) returns true becaus o,o1 references points to same object.
equals() is overridden into String & Wrapper Classes.
and equals() in String and All Wrapper classes compares the contents in the reference variable.

thats why equals() works differently on String & StringBuffer.
because equals() on StringBuffer takes equals() from Object and equals() on String takes the overridden method in String class.

[ March 01, 2005: Message edited by: Subbarao Anaparthi ]
[ March 01, 2005: Message edited by: Subbarao Anaparthi ]
 
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