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Wrappers and Primitives Problem

 
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when i try to access a[1],the output is 0,while there is a nullpointerexception when a1or b1 are accessed

WHY SO???
 
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'a' is table of primitives.
'a1' and 'b1' are tables of objects (Boolean, Integer, Char, Number etc. etc. are all descendants of Object).

Cells of table of primitive booleans are initialized to 'false'.
Cells of table of Objects (Booleans, Integers, Bytes, Longs etc.) are initialized to null.
When you try to access a table cell which is initialized to null, you get NullPioterException.


 
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mohitkumar gupta, What are the default values for primitive instance variable and object reference variables?
 
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all the array type are initialized to their default values.....

But in the second case you are creating a four refernce to a boolean object and they all will be pointing to null .
So when you try to fetch those values you are getting null pointer exception
 
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Pelase check the Java default values here: http://www.janeg.ca/scjp/lang/defaults.html
 
Shanky Sohar
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good link above to know the default value.
 
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