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Wrapper Classes

 
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Why do we need wrapper classes. Where we implement them. Are they useful for certification exam.
 
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The wrapper classes, Boolean, Byte, Short, Character, Integer, Float, Double are used anytime you need to represent a primitive value as an Object.
Yes, the exam does include questions on wrapper classes.
The next version of my mock exam will have a new set of questions on the Byte wrapper class. I hope to have it up by 5:00 PM Pacific Time today, Friday, August 9.
 
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Please read read this about Wrapper Classes and come back if things are not clear.
It's not perfect but will help to get the basic ideas.
Try Dan's exam.
-Barry
[ August 09, 2002: Message edited by: Barry Gaunt ]
 
suresh kamsa
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Is wrapper objects are immutable?
 
Dan Chisholm
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Yes, the wrapper classes, Boolean, Byte, Short, Character, Integer, Long, Float, and Double are immutable.
 
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You will need a wrapper class anytime you want to store a primitive type (such as int or double) in a collection (such as a Set , List, or Map).
 
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