Define different main method format in Java

Do you know what do you mean of “public static void main()”?

Public

It  is “access specifier” ; so it is basically define the scope of methods, classes and interface and etc.  you know JRE (Java Run-time Environment) is the outside part of class. if we use other access specifier (private, protected) so you can’t access the that class. If you are not used any access specifier. So compiler use the default access specifier.

Static

In class there are two type members

      1-Instance member
          represent attributes and behavior of individual object. By default all the      member of class is instance member.

     2-class member
          represent attributes and behavior of whole class. Denoted  by  “static”   keyword.

So static keyword are used define the class member.

Void

Functions are always requires a return type so void is one of them to returns value implicitly. If any error occur in the program so O.S returns the value with the help of  JRE.

Main:

only method name

Are you know the given below syntax are valid or not valid  in JAVA?

Syntex-(Modifier ReturnType MethodName() )

Static public void main (String [] arg ) true

Static public void main(String[][] arg) runtime error NoSuchMethodError

Static void public main (String [][] arg) compile time error

Void static public main (String arg[]) compile time error

 public static void main (String arg) runtime error NoSuchMethodError

Public void static main ([] String arg) compile time error

Public static void main (String[] arg[]) runtime error NoSuchMethodError

Public static void main() runtime error NoSuchMethodError

                                                 Author-Ravi Kumar

Basic Interview Question in Java

Introduction

Java, now it’s time to play with JAVA. I started with a new existing point.

Can we use multiple main in a program

Yes; we can use multiple “main()” method in a java program. But the both main methods argument should not be same, as you know, the  java programs execution is start from “main()” method means (public static void main(String arg[]), then simply declare the second ‘main()” method in this main method for execution, Now the given below example shown you how to do it.

Example

 class A

{

public static void main(String arg[])

{System.out.println("welcome");

main();

}

public static void main()

{

System.out.println("first");

}

}

Output

Can we run the program without main(String [] args) method

Yes we can run a java program without  main() method. Because java provide a functionality with the use of “static” keyword and that “static” keyword can be a block or static data member or static method,  firstly execute whenever you compile a  java program. Let’s see, it works or not.

Example

 class A

{

static

{

System.out.println("welcome");

System.exit(0);

}

}Output

Can we change the main thread name?

Yes, we can change the main thread name.

Can we print the message before the main method execution?

Yes, we can print the message before the main method. Let’s see how

Example

class A

{

static

{

System.out.println("welcome");

}

public static void main(String arg[])

{System.out.println("main method");}}Output

Author-Ravi Kumar