import java.io.*;

public class Rename {
   public static void main(String argv[]) throws IOException {
     if(argv.length!=2) {
       System.out.println("Usage: java Rename <src> <dest>");
       System.exit(1);
     }
     File src = new File(argv[0]);
     File dest = new File(argv[1]);
     if(!src.exists()) {
       System.out.println(src+": No such file");
       System.exit(1);
     }
     if(dest.exists()) {
       System.out.println(dest+": already exists");
       System.exit(1);
     }
     if(!src.renameTo(dest)) {
      System.out.println("Failed....");
      System.exit(1);
     }
   }
}