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immutable

Madhu Sudhana
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Joined: Apr 16, 2006
Posts: 127
How can we make a class immutable?


"And the trouble is, if you don't risk anything, you risk even more." -- Erica Jong.
Shoumin Li
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Joined: Jul 06, 2007
Posts: 85
As I known,these are some rules for making a class immutable:
1. Don't provide any methods that modify the object (known as mutators).
2. Ensure that no methods may be overridden.
3. Make all fields final.
4. Make all fields private.
5. Ensure exclusive access to any mutable components.

[ July 25, 2007: Message edited by: Shoumin Li ]
[ July 25, 2007: Message edited by: Shoumin Li ]

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Madhu Sudhana
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Joined: Apr 16, 2006
Posts: 127
thanks for the reply.....

Can I assume that String class is following the rules you have mentioned?

or String class has some extra features............?
Ulf Dittmer
Marshal

Joined: Mar 22, 2005
Posts: 42946
    
  68
Originally posted by Madhusudhana E:
Can I assume that String class is following the rules you have mentioned?


Even better: looking at the javadocs of the String class you can find out for sure if these conditions are met.
 
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subject: immutable