Java programming challenge ! , given the number of rows, n, as input, write a program to print the following pattern.

Given the number of rows, n, as input, write a program to print the following pattern.

expected output:
       1
      1 2
     1   3
    1     4
     1   3 
      1 2
       1

public static void main(String[] args) {
   int n = Integer.parseInt(args[0]);

   for(int i=1;i<=n;i++)
   {
     for(int j=0;j<n-i;j++)
       System.out.print(" ");
     System.out.print(1);

     for(int j=0;j<2*(i-1)-1;j++)
     System.out.print(" ");

     if(i!=1)
     System.out.print(i+1);
     System.out.println();
   }
 }