Passing Arguments To Console In Java

Remember String [] args ?

• This allows to pass values from console to Java application in the form of Strings.
• You can use those arguments within Java application by the name of array (here args) and index number

  public class Main {  	public static void main( String[] args) {  		System.out.println(args[0]);  	}  }

• Console:
  
  • K:\>javac Main.java
  • K:\>java Main MyArgument
  • OUTPUT:
    MyArgument

Guess the output:

• Console:
  • K:\>javac Main.java
  • K:\>java Main My Argument
  • OUTPUT ?
    My Argument
• WRONG!
  • REAL OUTPUT:
    My
• Why?
  • Java separates arguments by spaces.
    My -> args[0]
    Argument -> args[1]
• How to make your desired output work?
  • Wrap your argument in double quotes:
    • K:\>java Main “My Argument”
• What would happen if you do this: 
  • K:\>javac Main.java
  • K:\>java Main
• Exception!
  • Exception in thread “main” java.lang.ArrayIndexOutOfBoundsException: 0
• Above exception is ‘Fatal Exception’
  • Solution: Error handling