How To Write A Simple Command Line Program In Java

Here is a simple program to process command line arguments in Java.

 public class CommandLine {  
      /**  
       * @param args  
       */  
      public static void main(String[] args) {  
           if(args.length>0&&args.length%2==0){  
             for(int i=0;i<args.length;i+=2){  
                  if(args[i].equals("-f")){  
                      System.out.println("Input File Name is : "+args[i+1]);  
                  }else if(args[i].equals("-o")){  
                       System.out.println("Output File Name is : "+args[i+1]);  
                  }  
             }  
           }else{  
                if(args.length>0){  
                 System.out.println("Mismatched arguments");  
                }else{  
                 System.out.println("No arguments specified. Exiting...");       
                }  
           }  
      }  
 }  

Execute as :

java CommandLine  -f C://abc/input.txt -o C://abc/output.txt

Output:

Input File Name is : C://abc/input.txt
Output File Name is : C://abc/output.txt