Question about do-while loop

[Milton Ochoa]

This is pretty

�Why cannot find the 'a' symbol (variable)?

...
do{
int a = 0;
System.out.println(a);
}while(a == 0);
...

----------------------------------
Test10.java:14: cannot find symbol
symbol : variable a
location: class Test10
}while(a == 0);
^
1 error
-------

[praveen Shangunathan]

You will have to declare 'a' before the do .

for eg.,
int a;
do{
a = 0;
System.out.println(a);
}while(a == 0);

[Petrus Pelser]

It's called variable scope. If you declare a variable inside a block, i.e inside braces {}, it will only be visible inside that block. In a do..while, or any other loop construct for that matter, the condition statement is clearly not inside the block and can thus not see any variables declared in that block.

[Milton Ochoa]

Thank you Mr. Petrus