Explain about Super Keyword in Java?
https://www.computersprofessor.com/2016/12/explain-about-super-keyword-in-java.html
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Super is a keyword.
Super is used at 3 levels:
1. Super at variable level
2. Super at method level
3. Super at constructor level
Super
at variable level :
To differentiate base class variable and subclass variables.
class SS
{
int a = 10 ;
}
class Bb extends SS
{
int a, b ;
void Ss ( )
{
a = 20 ;
b = 30 ;
System.out.println (a) ;
System.out.println (super. a) ;
System.out.println (b) ;
}
}
O/P : 20
10
30
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Super
at method level : To
differentiate base class methods & subclass methods.
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class Aa
{
int a = 10 ;
void display ( )
{
System.out.println (“base class
hai”) ;
System.out.println (a) ;
}
}
class Bb extends Aa
{
int b = 20 ;
void display ( )
{
super.display ( );
System.out.println (“Subclass hai”)
System.out.println (b) ;
}
}
O
/ P : Base class
hai
10
Sub
class hai
20
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Super
at constructor level :
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Super
( ) : super Calls
base class default constructor, super (– , –) calls base class parameterized
constructor.
class Aa
{
int a, b
Aa ( )
{
a = 10 ;
b = 20 ;
System.out.println (a) ;
System.out.println (b) ;
}
}
class Bb extends aa
{
int c;
Bb ( )
{
super ( ) ; // base class default constructor
c = 30 ;
System.out.println (c) ;
}
}
O
/ P : 10
20
30
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