this –

Definition- It’s a keyword which refers to current class.
this keyword is used to-
(1) Refer class variable –

package dis;

public class TisVar{
String name="java";

void show(){
System.out.println(this.name);
}
}

(2) Refer current class constructor-

package dis;

public class TisConst{

public TisConst(){
this(5);
System.out.println("a");
}

public TisConst(int age){
System.out.println("b");
}

public static void main(String[] args){
TisConst k=new TisConst();
}
}

(3) Invoke current class method-


package dis;

public class TisMtd{

void show(String name){

System.out.println(name);

}

void disp(){

this.show("a");

}

}

} 

(4)this : passed as an argument in method call


package dis;
public class TisMtdArg{
String n="a";

void show(String name){
System.out.println(name);
}

void disp(){
this.show(this.n);
}
}
}

(5)this : passed as an argument in constructor call


package dis;
public class TisConstArg{
int a=12;

void show1(){
new TisConstArg(this.a);
}

public TisConstArg(int age){
System.out.println("b");
}
}

(6)this: can be used to return the class instance


package dis;
public class TisClsIns{

TisClsIns currentIns(){
return this;
}
}

 

2]:- SUPER KEYWORD:-

Definition- It’s a keyword which refers to parent class.

super keyword is used to –
1:- Refer parent class instance variable.

package spr;
class SperVar{
int age =10;
}
public class SuprVar extends SperVer {
int age=20;
void show(int age){
System.out.println(super.age);
}
}
}

2:- Refer parent class constructor.

package spr;
class SperConst{
SperConst(){
System.out.println("a");
}
}
public class SuprConst extends SperConst {
SuprConst(){
super();
System.out.println("b");
}
public static void main(String[] args){
SuprConst s1=new SuprConst();
}
}

3:-Refer parent class method

package spr;
class SperMtd{
void show(){
System.out.println("a");
}

public class SuprMtd extends SperMtd{
void show(){
System.out.println("b");
}
public static void main(String[] args){
SuprMtd s1=new SuprMtd();
s1.show();
}
}

 

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