ADPROG
JAVA-METHODS
➢JAVA METHOD
- is a collection of statements that are
grouped together to perform an operation.
- When you call the:
“System.out.println(
)
method, for example, the system actually
executes several statements in order to
display a message on the console.
●Create own methods or without return
values
●Invoke a method with or without
parameters, and apply method
abstraction in the program design.
➢SYNTAX
public static int methodName(int a, int b)
{
//body
}
●public static - modifier
●int - return type
●methodName- name of the method
●a,b- formal parameters
●int a, int b - list of parameters
➢METHOD CALLING
- it should be called.
- there are two ways in which a method is
called:
●return a value or
●returning nothing (no return value)
- the process of “method calling” is simple.
- when a program invokes a method, the
program control gets transferred to the
“called method”
- this “called method” the returns control to
the caller in two conditions, when:
●return statement is executed
●it reaches the method ending closing
brace.
public class ExampleVoid{
Public static void main(String[]args){
methodRankPoints(255.7);
}
public static void methodRankPoints(double points){
If (points>=202.5){
System.out.println(“Rank:A1”);
}
Else if (points>=122.4) {System.out.println(“Rank:A2”);
}
else{
System.out.println(“Rank:A3”);
}
}
}
OUTPUT: RankA1
➢PASSING PARAMETERS BY VALUE
●While working under calling process,
arguments is to be passed.
●These should be in the same order as
their respective parameters in the
method specification.
●Parameters can be passed by value
or by reference.
●Passing Parameters by Value means
calling a method with a parameter.
●Through this, the argument value is
passed to the parameter.
public class swappingExample {
public static void main (String[] argos) {
int a = 30;
int b = 45;
System.out.println (“Before swapping, a = “+ a
+” and b= “+b);
swapFunction(a,b);
System.out.println(“\n**Now, Before and After
swapping values will be same here* * : ”);
System,out.println (“After swapping, a = “+a+”
and is “+b);
}
Public static void swapFunction (int x, int y) {
System.out.println(“Before swapping(Inside),
a= “+ a +” b = “+ b);
Int z= x; x=y; y=z;
System,out.println (“After swapping Inside), a
= “+a+”b = “+b);
●Write a Java method to display the
middle character of a string.
●If the length of the string is odd there
will be open middle character.
