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Increment

Vishnu Prakash
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Joined: Nov 15, 2004
Posts: 1026


Output: 1 1 0 1 1

I couldn�t understand how r2.b and b are evaluating to 1 and why r2.a is evaluating to 0.


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Mike Gershman
Ranch Hand

Joined: Mar 13, 2004
Posts: 1272
There are 2 instances (objects) of Red. r1 refers to the first. r2 refers to the other.

There are two copies of a, one in each object. r1.a refers to the first copy, r2.a refers to the other copy.

Thete is one copy of the static member variable b. It can be refered to as b, Red.b, r1.b, or r2.b, but there is still only one copy.

All three are member variables so they are initialized to 0. r1.a and the one and only b are then incremented to 1. r2.a is left at 0.

In the print line, the same b is printed three times.
[ January 02, 2005: Message edited by: Mike Gershman ]

Mike Gershman
SCJP 1.4, SCWCD in process
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: Increment