|
|
| Line 1: |
Line 1: |
| − | '''Collections and Generics'''
| |
| | | | |
| − | <u>equals() and hashcode() </u>
| |
| − |
| |
| − | * Mainly used for storing and retrieving objects from hashed collections.
| |
| − | * First object's hashcode is used to figure out which hash bucket the object is in
| |
| − | * Then the equals() method is used to compare objects in the same hash bucket.
| |
| − |
| |
| − | This means that:
| |
| − | * equal objects MUST have the same hashcode
| |
| − | * unequal objects can have the same (or different) hashcode (e.g. same bucket but objects are different)
| |
| − | * objects having different hashcodes MUST be unequal
| |
| − |
| |
| − | [[Category:OCPJP]]
| |
