Keyword Super

[Mike Sh]

Hello
If someone can explain to me the meaning of word super in Java?
I'm confused of this word

[Mike Curwen]

Super is used to refer to something in the superclass. Either a method or a variable.

public class SuperClass {
public int value = 5;
public void SayHello() {
    System.out.println("Hello World, From SuperClass");
    }
}

public class SubClass extends SuperClass {
public int value = 10;

public void SayHello() {
    System.out.println("Hello World, from SubClass");
    super.SayHello();
}
public void ShowValue() {
    System.out.println("Value in SubClass: " + value);
    System.out.println("Value in SuperClass: " + super.value);

}
public static void main (String args[]) {

    SubClass app = new SubClass();
    app.SayHello();
    app.ShowValue();
}
}

produces:

Hello World, from SubClass
Hello World, From SuperClass
Value in SubClass: 10
Value in SuperClass: 5

[Susan Delph]

Mike Curwen gave an excellent example.
Here's a graphical representation:

      Superclass
          |
    |-----|--------------|
    |                    |
   Subclass1     Subclass2

So, if I were writing the Subclass1 code, and I wanted to refer to a variable or method from the Superclass, I would refer to them as super.variable or super.method().
This is exactly what Mike did with the line:
System.out.println("Value in SuperClass: " + super.value);
Susan

[This message has been edited by Susan Delph (edited May 22, 2001).]