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Primary Key Class

Rajib Sarma
Ranch Hand

Joined: Apr 29, 2002
Posts: 34
Why do we need to override the methods equals() and hashCode() for a primary key class?

*** Rajib Prasad Sarma ***<br />==========================
Snigdha Solanki
Ranch Hand

Joined: Sep 07, 2000
Posts: 128
Primary Key Class need to override hashCode() so that it can be stored in a Hashtable. Container internally stores all the entity beans it has in memory in a hashtable or some similar structure.
Similarly,primary key class need to override equals method as container calls this method to compare two primary keys so as to determine if two cached entity beans represent the same data.

Snigdha<br />Sun Certified Programmer for the Java™ 2 Platform
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subject: Primary Key Class
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