How do I change a variable from a try in java?

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Hey everyone, im trying to change the value of a variable from within a try statement so that it will effect the variable outside of the try, does anyone know how to do this?

Posted 6-Feb-12 8:38am

Sicppy

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CPallini · Accepted Answer · 2012-02-06T09:55:00

Solution 1

The try block (like any other block of statements) may access outer blocks variables. On the other hand if you define a variable inside the try block itself then you cannot change it outside (see, for instance here[^]).

Posted 6-Feb-12 9:55am

CPallini

Comments

Sicppy 6-Feb-12 16:08pm

I already tried that, but the changes only effect what is inside the try block. for example if I ran this code(just pretend that the syntax is right)

String x = hi;
try {
x = goodbye;
}
System.out.println(x);

The outcome would still be hi

TorstenH. 7-Feb-12 2:06am

Your code has an init-value that remains if the try/catch is failing. That is OK, but hard to detect when the catch doesn't make a clear announcement(like forcing a popup). It's better to init on "null"/-1 which is a non valid value and easy to figure in further operations.

CPallini 6-Feb-12 17:02pm

How could you run it if the syntax is wrong (it is in fact wrong). The following (contrived) example:

int x=10;
try
{
x=15;
}
catch(Exception e)
{
}
int p = x;

assigns 15 to p.
I've tested it.

Sicppy 9-Feb-12 14:34pm

it was just an example, I have it set up the right way in my actual program. It sets a string. assign's it a value from within a try, but it says the variable isn't initialized when i try System.out.println(x);
from outside of the try block

CPallini 9-Feb-12 15:08pm

Well, then please post the actual code, in order to let me make a test.

Sergey Alexandrovich Kryukov 6-Feb-12 18:50pm

Hard to say where OP was confused, this is way too simple. My 5 anyway.
--SA