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null in a boolean?

keerthidhar dongre
Greenhorn

Joined: Jan 30, 2002
Posts: 26
public static void main(String args[])
{
Boolean a[]=new Boolean[4];
int I=1;
System.out.println(a[I]);
}
Why does this print null? when the only values a boolean can hold are true and false? Also why does this compile since the array elements are not initialized?
Thanks in advance,
Keerthi
Manish Hatwalne
Ranch Hand

Joined: Sep 22, 2001
Posts: 2578

Boolean is a wrapper class and boolean is primitive which can hold only true or false. What you have is an array of 4 Boolean type object references.
Arrays are always initialized, even if they are local to the method.
HTH,
- Manish
keerthidhar dongre
Greenhorn

Joined: Jan 30, 2002
Posts: 26
Thanks a lot Manish.
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: null in a boolean?
 
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