Command Line arguments in Java

If we run a Java Program by writing the command “java Hello Geeks At GeeksForGeeks” where the name of the class is “Hello”, then it will run upto Hello. It is command upto “Hello” and after that i.e “Geeks At GeeksForGeeks”, these are command line arguments.

When command line arguments are supplied to JVM, JVM wraps these and supply to args[]. It can be confirmed that they are actually wrapped up in args array by checking the length of args using args.length

// Program to check for command line arguments
class Hello
{
    public static void main(String[] args)
    {
        // check if length of args array is
        // greater than 0
        if (args.length > 0)
        {
            System.out.println("The command line"+
                               " arguments are:");

            // iterating the args array and printing
            // the command line arguments
            for (String val:args)
                System.out.println(val);
        }
        else
            System.out.println("No command line "+
                               "arguments found.");
    }
}

When executed as following:
java Hello Geeks at GeeksforGeeks
Output:

The command line arguments are:
Geeks
at
GeeksforGeeks

When executed as following:
java Hello
Output:

No command line arguments found.

This article is contributed by Twinkle Tyagi. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

GATE CS Corner    Company Wise Coding Practice

Recommended Posts:







Writing code in comment? Please use ide.geeksforgeeks.org, generate link and share the link here.