I have defined an object and declared a static variable i
. In the get()
method, when I try to print the instance and class variable, both print the same value.
Isn't this.i
an instance variable? Should it print 0 instead of 50?
public class test {
static int i = 50;
void get(){
System.out.println("Value of i = " + this.i);
System.out.println("Value of static i = " + test.i);
}
public static void main(String[] args){
new test().get();
}
}
No, there's only one variable - you haven't declared any instance variables.
Unfortunately, Java lets you access static members as if you were accessing it via a reference of the relevant type. It's a design flaw IMO, and some IDEs (e.g. Eclipse) allow you to flag it as a warning or an error - but it's part of the language. Your code is effectively:
System.out.println("Value of i = " + test.i);
System.out.println("Value of static i = " + test.i);
If you do go via an expression of the relevant type, it doesn't even check the value - for example:
test ignored = null;
System.out.println(ignored.i); // Still works! No exception
Any side effects are still evaluated though. For example:
// This will still call the constructor, even though the result is ignored.
System.out.println(new test().i);
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