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Question ID :957734680770

 
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Hey guys
I can't understand why this compiles "correctly" and donot give error of redeclaring of "i".
static int x = 5;
public static void main(String[] args)
{
int x = ( x=3 ) * 4;
System.out.println(x);
}
Regards Denish.
 
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Java allows you to redeclare variables, but you need to be careful about the scope. The x local to the method is only valid within the method. You can access the class variable x within the method by using this.x.
 
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I think Lance is correct (the non-static x is local to the main method and is therefore not the same as the class variable x), except that since the class variable is static, you can't access it with the this keyword, which references an instance of the class. The class name is not supplied, but you would reference the static variable x as Classname.x rather than this.x.
 
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Scott,
You have rightly summed it.
"this" is not accessible to the static member of a class as it is the instance variable.
Ravindra Mohan.
 
Lance Finney
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I forgot that main itself was static. Wouldn't my statement be true if the method weren't static?
For example, the following code returns 1 and 0. Although the variable is static, "this" has a link to it.
public class Test
{
static int i = 0;
public static void main(String[] args)
{
Test t = new Test();
t.amethod();
}
public void amethod()
{
int i = 1;
System.out.println(i);
System.out.println(this.i);
}
}
 
Greenhorn
Posts: 24
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Originally posted by Lance Finney:
I forgot that main itself was static. Wouldn't my statement be true if the method weren't static?
For example, the following code returns 1 and 0. Although the variable is static, "this" has a link to it.
public class Test
{
static int i = 0;
public static void main(String[] args)
{
Test t = new Test();
t.amethod();
}
public void amethod()
{
int i = 1;
System.out.println(i);
System.out.println(this.i);
}
}


Yes because non static members have access to static members but not vice versa.
Vivek
 
denish mehta
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Thanx a lot guys for such a good explainations
Denish
 
mister krabs
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Originally posted by Scott Appleton:
since the class variable is static, you can't access it with the this keyword, which references an instance of the class. The class name is not supplied, but you would reference the static variable x as Classname.x rather than this.x.


This is incorrect. Static variables can always be accessed through an instance of the class but you still get the one and only static variable.

 
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