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equals() and hashCode() contract

 
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class F {
public static void main (String[] args) {
Short s1 = new Short("1"), s2 = new Short("1");
int a1 = s1.hashCode(), b1 = s2.hashCode();
System.out.printa1==b1);

}}

Answer is "true" .How?
Is it because of equals() and hashCode() contract??
 
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Hi.

When you invoke hashCode() on objects that are equals(), the result (which is an integer) must be the same.
[ June 13, 2007: Message edited by: Leandro Melo ]
 
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Yes. This is what the javadoc specifies about hashCode():


If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result.
[/code]

 
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