Explanation
Till now as we know that, in java we have a main method called main function.But in java we also use some codes to do some separate task. So thats why here comes Method.
Difinition
A method is a set of code which is referred to by name and can be called (invoked) at any point in a program simply by utilizing the method's name. Think of a method as a subprogram that acts on data and often returns a value. Each method has its own name.
you can use many methods in a simple program.
parts of method
Parts of method mean's, In java method there are some parts ( codes ), Which java method is made.Like modifier, return part,name part,pass value and a body.Method is simply just made of these things.
Method condition
1.A method can't be in main function
2.If a method is an int method so it should has a return statement
3.If a method is void. So it's mean no return value should be use.
4.You can create many methods in a program
5.If a method is private so it's mean it can't be access out of Class
6.if a method is static so you can access it from anywher
7.You can call a Method many times.
Simple out put Method
So now here I am going to show you how to create a method without any return value andpassed value let's have a look at this example
package myPackage;
public class myClass{
public static void main(String[]args){
}
public static void myName(){
System.out.println("Abdul wahab");
}
}
Example explanation
In this example myName is the name of the function.and in the function body as I print out "abdul wahab" so this means..that this method would just print out Abdul wahab.And now if you run this, So it won't work.Because we haven't called this method yet.So to call this method pretty simple.See this example
package myPackage;
public static void main(String[]args){
myName();
}
static void myName(){
System.out.println("Abdul wahab");
}
Now it will show something like this to the console if you are using eclips, As shown below
You can call a method many times its upto you as much as you need.Look at the Example
package myPackage;
public class myClass{
public static void main(String[]args){
myName();
myName();
myName();
}
static void myName(){
System.out.println("Abdul wahab");
}
}
And it would show to the console as below
Method with String variable
You can use a variable also in a method.like below I am gonna show you a Stringvariable,How you can print out a String variable in methods.
package myPackage;
public class myClass{
public static void main(String[]args){
myName();
}
static void myName(){
String a="my name is abdul wahab";
System.out.println(a);
}
}
It would print out something like this.If you are using Eclips
passing a value to void method
Explanation
Passing a value to a void method is mean to put variables in the parameters of a method ie
package myPackage;
public class myClass{
public static void main(String[]args){
}
static void myMethod(int d){
}
static void myName(String name){
}
static void towValues(int height,int width){
}
}
So as you can see these are some simpleExamples about where we pass values in a method. Iam sure you got the idea!
.
As we are clear about how to passes values in methods.Now this is the time to know how to use them.Why we passes values in a method. I will make this pretty clear with some Examplesbelow
package myPackage;
public class myClass{
public static void main(String[]args){
What we did here? In the parameter of the method(myMethod).We just created an int variable named it number, .And then we print out the number variable. Then we called this method from the main function.and we passed a value 5 as a parameter. And then we recall the method and this time we passed a new value 88.And now if we run this so it would give us a result as shown below
passing many int variables in methods
You can pass many variable in a single methods.Just put commas in between each variable.ie
package myPackage;
public class myClass{
public static void main(String[]args){
myMethod(8,8);
}
static void myMethod(int a,int b){
System.out.println(a+b);
}
}
What you need to do, 1.Create a method. 2.pass two int variable a and b. 3.In print out add them. 4.And call them in main,and make sure to give some values other wise it cannot proccess with a and b. I put (8,8). 5.And that set.
And now if you run this so it should be like this
passing String in method
Explanation
You can pass a String variable as well into the parameter of a me thod.Like in below ExampleI am gonna be passing a String variable to the method as a parameter
what you have to do is just you have to put String instead of int ie
package myPackage;
public class myClass{
public static void main(String[]args){
myMethod("abdul wahab");
/*put your name in double quotes
as a parameter*/
}
static void myMethod(String name){
System.out.println(name);
}
}
What we have done here? We just put a String variable into the method as a parameter,named it number. and then we print out we then called this method from the main function. And we gave value as "abdul wahab".Now if you run this so it would look like the same as shown below
Passing String and int both in a method
You can pass all types of variables an int,String and double etc in a single method.Have a look at the Example below
package myPackage;
public class myClass{
public static void main(String[]arga){
myMethod(String health,int age){
if(health=="good"){
System.out.println("congrats you can come");
if(age>33){
System.out.println("you are old");
}
else{
System.out.println("you are out");
}
}
else{
System.out.println("you can come");
}
}
}
Here we passed two different types of variables in a single method.And it works perfect and fine.So its mean you can pass many types of variable in a single method
Methods with return type
There is another type of method in java programming.In which we get a value back as return.Let's have a look at the example below.While in this example I am gonna be returning an int back to my main function.ie
package myPackage;
public class myClass{
public static void main(String[]args){
System.out.println(myMethod());
}
static int myMethod(){
return 8;
}
}
As you saw we created an int method in which we return a value 8 and then we called this return value from the main method and now if we run this so it would print out
Return String method
You can create a String method as well in java programming which will return a value back to you as shown below
package myPackage;
public class myMehtod{
public static void main(String[]args){
System.out.println(myMethod());
}
static String myMethod(){
return "how are you?";
}
}
I hope it makes scence to you.method is the same.We just put String instead of an int, and if you run this so it would print out
Passing a value to the void method
As i discussed already there are some parts of a method modifier, return type,name of method , parameter list and a body ofcource. Now here we'll go over what a parameter list is and how to use it in a method.So first of all the parameter list can be known as the codes in the round braces.ie
package myPackage;
public class myClass{
public static void main(String[]args){
}
static void myMehtod(){
}
}
So now as you got the idea about what a parameter list.Now this is the time for how to use.So for this let see this example first
package myPackage;
public class myClass{
public static void main(String[]args){
myMethod(8);
}
static void myMehtod(int number){
System.out.println(number);
}
}
After run this is the result for you
So what we did here, we createed a parameter list with an int named number..And then in the method body we printed out the number.And then we called this method up in the main function. But (notice this) make sure.It will take an int value as a parameter.As i put 8 in theexample above.
As well as you can pass two values or many values in a single method ie
package myPackage;
public class myClass{
public static void main(String[]args){
myMethod(10,4,4);
}
static void myMethod(int a,int b,int c){
System.out.println(a+b-c);
}
}
As a result you will get
Passing value using different data types in a method
You can pass different data types in a singlie method.What this mean is actually if you need a method in which you wanna use all the data types like String, int and double etc.So yeah let's see an example for to make yourself clear about this.
package myPackage;
public class myClass{
public static void main(String[]args){
myMethod("your total is ",10,2.8);
}
static void myMehtod
(String a,int b,double c){
System.out.println(a+(b-c));
}
Now let's run this
Passing values into return type method
To pass a value into return type method is also the same as we did in void but this time the method is change.In this method we'll get return something, to return something put return at the end of your method, otherwise it wont work ,and also put int instead of void..ie
package myPackage;
public class myClass{
public static void main(String args){
System.out.println(myMethod(8));
}
public static int myMethod(int number){
return number;
}
}
Here we have a method,which is obviosly a return type,Now in this method we passed an int variable (name=number) as a parameter.And then we return the number.And in the main method we printed out this method with value 8.Now let's run and see!
You can pass and return two or more than two values as well like below
package myPackage;
public class myClass{
public static void main(String[]args){
System.out.println(myMethod(3,9));
}
public static int myMethod(int height,int width){
return height*width;
}
}
And if you run it would show
So this was a simple example i am sure nothing here to explain.But if you really want to know more about this.leave me a comments below.
Use of Scanner Object in a return type method
Now this is another Example and in this Example I am gonna be showing you using of Scanner object in a return type method
package myPackage;
import java.util.Scanner;
public class myClass{
public static void main(String[]args){
Scanner d= new Scanner(System.in);
System.out.println("types in three numbers")
int a= d.nextInt();
int b=d.nextInt();
int c=d.nextInt();
myMethod(a,b,c);
}
static int myMethod(int a,int b,int c){
if(a>b && b>c){
System.out.println("b is bigger");
}else if(b>a && b>c){
System.out.println("b is bigger");
}else{
System.out.println("c is begger");
}
return 0;
}
}
And now if you run this
So yeah that's all for a method....If you have any problem belong to this topic ,or related to java you can leave me a comment and i would answer all your questions in very short time
If right now if you have any problem just contact me i have given the contact form in each of my page.So just click on that and leave me a comment or just message me and trust me.i'd love help you out from every difficulties you have..
