Why we use super in java?

Answer 1

The keyword super is used to refer to the parent class instance of the current class.

Lets say we have a class

class A extends B {

...

public void getName(){

}

...

}

Lets assume the parent class B also has a method getName()

Inside class A if you call getName() it would by default call the current class's method. To make the JVM intentionally call the super class method we can use super

if we say super.getName() then the parent class instance of the method would be called.

Answer 2

super keyword is used for two reasons:

1. To Call the super class or base class constructor

2.To call super class methods.

If you don't create constructor in a class...Java automatically put for you.

Always remember..that the first statement in derived class constructor must be a call to super or this.

Answer 3

The super keyword is used to refer to the superclass of the current class. Common uses include when extending from a Component. The paint() method may need to be overridden, but the parent's paint method still needs to be called.

class MyFrame extends JFrame() {

public void paint(Graphics g) {

super.paint(g);

// do our specialized paint here

}

}

Answer 4

Super refers to the parent class object instance. In case of static methods, they do not belong to any object instance and hence they cannot call anything related to the parent class instance.

Answer 5

These are two different things.

"Super" is used in inheritance - if class B inherits from class A, and we want the constructor of B to do the same things the constructor of A does (and maybe more things), we can call A's constructor in B's constructor:

public B() {

super();

......

}

Notice that it must be the first line in B's constructor.

"This" is used in case of overloading, to call a function aith the same name.

For example, if we have a constructor that receives one argument, and we it want to have a default value of 0, we can write:

public C() {

this(0);

}

Answer 6

"super " is a key word in java. this is used for referring to super class members ( variables and methods ) from subclass .( when sub class and super class have members with same names).

Answer 7

Super refers to the base class of your object. For example, if you have a class named Foo...

@Override

public String getClassName()

{

String thisClass = "Foo";

String baseClass = super.getClassName();

return thisClass + ", which derives from " + baseClass;

}

...which derives from base class Bar...

public String getClassName()

{

return "Bar";

}

... calling Bar.getClassName would print "Bar", while calling Foo.getClassName would print "Foo, which derives from Bar".

Answer 8

super is a keyword in java.uses of super are:

1.it is used to call super class constructor.

2.It is used to call a method of super class that is hidden by sub-class.