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Doubt with static initializers

 
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public class Test {
static {int a=5;}
public static void main(String args[]{
System.out.println(a);
}
}

Is this legal,is it true that a variable declared in a static initializer is not accessible outside the enclosing block.
 
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Originally posted by vinayak manda:
public class Test {
static {int a=5;}
public static void main(String args[]{
System.out.println(a);
}
}

Is this legal,is it true that a variable declared in a static initializer is not accessible outside the enclosing block.



Extend this concept beyond a static variable to any variable that is declared within the curly braces. The curly braces provide the scoping context for the variable lifetime. It really doesn't matter if it is a static variable or not. For example, if I add a bit more code to your example:

I will get the same error as I did for a.
 
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It really doesn't matter if it is a static variable or not.



But what does static {int i=0} mean?
 
vinayak manda
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It is way of initialising the static variables in a method block.And where i as defined in the block is one copy per class (NOT ONE PER OBJECT)
 
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In your example, a is *not* a static field, but a *local* variable of the static initializer.

A static initializer is simply a block of code that will be executed when the class is loaded.
 
vinayak manda
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You mean that I can declare both local variables and static variables in static initializers.
I shouldn't be declaring instance variables in it ,right?.
As class is loaded,static block will execute ,it will initialize the variables to thier defautls when not initialized expicitly.

Correct me If I'am wrong.
 
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Any variables declared in a static initializer will be local to that block. You can initialize -- assign a value to -- a static variable in such a block, but it must be declared at class scope.
 
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Perhaps this is more clear to you.
b and c are declared outside the static initializer.
You need a static block only to use conditionals (if, while, for, ...).
static b = Foo.getSize (); might be declared and initialized without a static block.
 
Ilja Preuss
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Originally posted by Stefan Wagner:
You need a static block only to use conditionals (if, while, for, ...).



They are also often used to initialize collections:

 
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