Java Reference
In-Depth Information
}
void printX() {
System.out.println(x + " " + super.x);
}
}
This program produces the output:
4.7 2
because the declaration of
x
in class
Test
hides the definition of
x
in class
Point
, so class
Test
does not inherit the field
x
from its superclass
Point
. Within the declaration of class
Test
, the simple name
x
refers to the field declared within class
Test
. Code in class
Test
may refer to the field
x
of class
Point
as
super.x
(or, because
x
is
static
, as
Point.x
). If the
declaration of
Test.x
is deleted:
class Point {
static int x = 2;
}
class Test extends Point {
public static void main(String[] args) {
new Test().printX();
}
void printX() {
System.out.println(x + " " + super.x);
}
}
then the field
x
of class
Point
is no longer hidden within class
Test
; instead, the simple
name
x
now refers to the field
Point.x
. Code in class
Test
may still refer to that same
field as
super.x
. Therefore, the output from this variant program is:
2 2
Example 8.3.1.1-3. Hiding of Instance Variables
class Point {
int x = 2;
}
class Test extends Point {
double x = 4.7;
void printBoth() {
System.out.println(x + " " + super.x);
