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Static variable

 
Stephane Weber
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Hi, in the following code :
public class Test {
static int total = 10;
public static void main (String args []) {
new Test();
}
public Test () {
System.out.println("In test");
System.out.println(this);
int temp = this.total;
if (temp > 5) {
System.out.println(temp);
}}}
A.The compiler reports an error at line 2
B.The class will not compile
C.The value 10 is one of the elements printed to the standard output
D.The compiler reports an error at line 9
E.The class compiles but generates a runtime error
Can anyone explain why the answer is C and not D ?
Thanks

Stephane
 
Corey McGlone
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Originally posted by Stephane Weber:
int temp = this.total;

You don't have line numbers, but I'll presume that this is the line in question.
This works because we're taking the value of a static variable and assigning it to a local variable. The static variable is initialized when the class is loaded so we are guaranteed that this variable contains the value 10 by the time we reach this line.
You get in trouble if you try to reference an instance member from a static context, but that isn't the case here. Rather, we're accessing a static member from a non-static context. That's fine.
Was that what your confusion was about or was it regarding the use of the keyword "this"?
I hope that helps,
Corey
 
manasa teja
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In the body of the method, the keyword this can be used like any other object reference to access the object.
In this example,
int temp = this.total;
is same as
int temp = Test.total;
HTH,
murthy
 
Stephane Weber
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Indeed my confusion was that I would have expected :
int temp = Test.total
Now I know it's all the same

Thanks
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