Functions/Methods
------------------------------------
println()
nextInt()
length()
CharAt()
length()
"Besant technologies"
---->Methods is a block of code that perform some specific task.
Employee management.
Wipro,TCS,...
login()
logout()
-------------------------------------
types:
----------
1)predefined function
2)user defined function
1)predefined function
----------------------------------------
---->These Functions are defined by java library.
2)user defined function
-----------------------------------------
These functions are created by user requirement
main method
------------------------
public static void main(String[] args)
{
syntax:
----------------
public static datatype method_name(list of arg)
{
//statements
}
public---->access specifier
static --->keyword
datatype---->int,float,void,char
void---->does not return any value
int,float,char,..--->it returns any value
method_name ---->valid name
list_of arg --->parameter.
public class Myclass3
{
public static void main(String[] args)
{
System.out.println("Welcome to Main method")
}
public static void mymethod1()
{
System.out.println("This is User Defined Method");
}
Output
-------------
Welcome to Main method
How to calling a userdefined method?
---------------------------------------------------------------
methodname();
EX:
-----
public class Myclass3
{
public static void main(String[] args)
{
System.out.println("Welcome to Main method")
}
public static void mymethod1()
{
System.out.println("This is User Defined Method");
}
}
-----------------------------------------------------------------------------
public class Main
{
public static void main(String[] args)
{
mymethod2();
System.out.println("Hello World");
mymethod1();//calling a method
}
public static void mymethod1()
{
System.out.println("This is userdefined method");
}
public static void mymethod2()
{
System.out.println("This is method2");
}
}
-------------------------------------------------------------
public class Main
{
public static void main(String[] args)
{
add();
}
public static void add()
{
int x=100,y=200;//functional variable
System.out.println(x+y);
}
}
-------------------------------------------------------------------
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
System.out.println("This is main method");
add(45,89);
add(5,3);
add(9,6);
public static void add(int x,int y)//x=45,y=89
{
System.out.println(x+y);
}
-------------------------------------------------------------------------
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
Eligible_to_vote(55);
Eligible_to_vote(12);
public static void Eligible_to_vote(int age)
{
if(age>=18)
{
System.out.println("Eligible for voting...");
}
else
{
System.out.println("Not Eligible for voting");
}
}
---------------------------------------------------------------------
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
int a;
Scanner sc=new Scanner(System.in);
System.out.println("Enter the value");
a=sc.nextInt();
Eligible_to_vote(a);
}
public static void Eligible_to_vote(int age)
{
if(age>=18)
{
System.out.println("Eligible for voting...");
}
else
{
System.out.println("Not Eligible for voting");
}
}
---------------------------------------------------------------------
return type
-----------------------
syntax:
----------------
return value;
EX:
-----
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
cube(10);//calling function
System.out.println("The value is:"+cube(10));
}
public static int cube(int n)
{
return n*n*n;//return 10*10*10-->return 1000
}
}
EX:
-----
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
Mymethod1(12.3f);
System.out.println("The Result is "+Mymethod1(12.3f));
public static float Mymethod1(float n)
{
return n*8;//
}
}
----------------------------------
EX:
----
package Mypack1;
import java.util.Scanner;
public class Myclass3
{
public static void main(String[] args)
{
Mymethod1(3);
System.out.println("The Result is "+Mymethod1(3));
public static float Mymethod1(int n)
{
return n*8;//
}
}
