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Can I pass a variable to to a method?

 
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I was wondering if there was a way I could pass the variable as a parameter as opposed to just the value e.g.

public void testvar () {
int testval1 = 1;
testvar2(testval1);
System.out.println(testval1); //I want this to print '2'
}

public void testvar2 (int testval) {
testval2 = 2;
}

Thanks in advance

Paul.
 
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make public int testvar2() instead.
If you want to pass it as a parameter, you could use a wrapper like the Integer class.
 
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no you can not pass by reference.
You could do:


instead (using return value instead of void).

Or you can pass in a Mutable Object and modify the state of the Object.




Just two ways how you could do it... you have to decide which/why/what... :-)


pascal
 
pascal betz
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If you want to pass it as a parameter, you could use a wrapper like the Integer class.



Integer is imutable.

pascal
 
Christophe Verré
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Integer is imutable.


My miss
Thanks for pointing it out.
 
(instanceof Sidekick)
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The wrapper direction is good, but you'd have to make your own mutable structure.

Method2 cannot change the holder variable to point to a different IntHolder, but it can change the contents of the IntHolder that both methods have reference to.
 
author and iconoclast
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Lazy /me will generally use a one-element array instead of an "XHolder" class.
 
Stan James
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D'oh, that is a lot cleaner, fer sure.
 
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