Little scope problem here
a is an instance member which means that if you modify it within a method its value will be changed. You also pass b by value but you also name the argument "b" so inside the method b will be the argument and not the instance member and that's why the value of b (the instance member) does not change.
If you refer to b inside the method then the actual b you are working on is the argument and not the instance member.
HIH
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Valentin Crettaz
Sun Certified Programmer for
Java 2 Platform