Pattern 20 - Even nos input causing trouble

#1

My code is working fine but is causing trouble with even nos, can you please review it

#3 
package pattern_practice_questions;

import java.util.Scanner;

public class Pattern20 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int nsp1 = n / 2;
        int nsp2 = 0;
        int rows = 1;
        while(rows<=n){
            for(int csp = 1;csp<=nsp1;csp++){
                System.out.print(" ");
            }
            System.out.print("*");
            for(int csp = 1;csp<=nsp2;csp++){
                System.out.print(" ");
            }
            if(rows!=1 && rows!=n){
                System.out.print("*");
            }
            System.out.println();
            if (rows<=n/2){
                nsp1--;
                nsp2+=2;
            }else{
                nsp1++;
                nsp2-=2;
            }
            rows++;
        }

    }
}
#4

for such patterns, you don’t need to code for even numbers. Because there is no suitable pattern for even nos.