args in the main() method

This might be a complex question. I hope someone can give me a simple answer. I want to know what this code means?
public static void main(String[] args){
     if(args > 2.length){
     // ect...
I understand that the main() method creates an array of strings.
How the table get filled?
What are filling up with?
Principal is the starting point for the program and if this table String whence?
How a table can be created before the program begins?

SquareBox wrote:
This might be a complex question. I hope someone can give me a simple answer. I want to know what this code means?

public static void main(String[] args){
if(args > 2.length){
// ect...

Next time, copy and paste, rather than re - type. That does not even compile. Probably you meant

if (args.length > 2)

I understand that the main() method creates an array of strings.

N °

He receives a reference to an array of strings as a parameter. As with any other method receives its parameters. The table is created before the method is called. There is nothing special about main() as Java language is concerned. It's only the JVM that attaches special significance to it.

How the table get filled?

The JVM it fills arguments it receives from the OS/shell on the command line before you call your main() method.

When you run

java ABC 123 MyClass

the java executable is called, and the operating system will go "ABC", "123" and "MyClass" to her shell. (In fact, I think that it can also pass "java", but whatever). The JVM then load MyClass, creates an array of strings containing "ABC" and "123", and the call of the main() method of MyClass by passing a reference to this String [].

What are filling up with?

See above.

Principal is the starting point for the program and if this table String whence?

See above.

How a table can be created before the program begins?

main() is the starting point for your application that runs inside the JAVA virtual machine. It is not the starting point for the JAVA virtual machine, the shell or the operating system, working together create this table and deliver a reference to it in your main() method.

Tags: Java

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