class
- Variables
- methods
- constructors
1. this keyword on Variables
- this keyword we can apply on variable to refer current class instance variable.
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Program : this keyword
Program name : Student1.java
Output :
Id is :1
Name is :Sravan
Id is :2
Name is :Amar
class Student1
{
int id;
String name;
Student1(int id,String name)
{
this.id = id;
this.name = name;
}
void display()
{
System.out.println(“Id is :”+id);
System.out.println(“Name is :”+name);
}
public static void main(String args[])
{
Student1 s1 = new Student1(1,"Sravan");
Student1 s2 = new Student1(2,"Amar");
s1.display();
s2.display();
}
}
Compile : javac Student1.java
Run : java Student1
Output :
Id is :1
Name is :Sravan
Id is :2
Name is :Amar
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2. this keyword on methods
- By using this keyword we can call current class methods.
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Program : this keyword
Program name : One.java
Output :
method is invoked
class One
{
public void method1()
{
System.out.println("method is invoked");
}
public void method2()
{
this.method1();
}
public static void main(String args[])
{
One o=new One();
o.method2();
}
}
Compile : javac One.java
Run : java One
Output :
method is invoked
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Note :
- If we didn't write this keyword then compiler will place this keyword implicitly.
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3. this keyword on constructor
- By using this keyword we can call current class methods.
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Program : this keyword
Program name : Two.java
Output :
default constructor
int param constructor
class Two
{
Two()
{
System.out.println("default constructor");
}
Two(int i)
{
this();
System.out.println("int param constructor");
}
public static void main(String args[])
{
Two t=new Two(10);
}
}
Compile : javac Two.java
Run : java Two
Output :
default constructor
int param constructor
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Thanks for your time.
Nireekshan