The code is very simple. Try this
import java.io.*;
public class myDiamondInput {
public static void main(String [] args) throws IOException {
BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));
String input;
int num;
System.out.println("input number: ");
input = stdin.readLine ();
num = Integer.parseInt(input);
int d = num;
int e = 0;
for (int a = 0; a <= num; a++) {
for (int c = d; c>= 1; c-- )
System.out.print(" ");
d-=1;
for (int b = 1; b <= a; b++)
System.out.print ("* ");
System.out.println();
}
num-=1;
for (int a = 0; a<=num; a++) {
for (int b = num; b > a; b--)
System.out.print (" *");
System.out.println();
for (int c = 0; c <= e; c++)
System.out.print(" ");
e+=1;
}
}
}
import java.io.*;
public class myDiamondInput {
public static void main(String [] args) throws IOException {
BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));
String input;
int num;
System.out.println("input number: ");
input = stdin.readLine ();
num = Integer.parseInt(input);
int d = num;
int e = 0;
for (int a = 0; a <= num; a++) {
for (int c = d; c>= 1; c-- )
System.out.print(" ");
d-=1;
for (int b = 1; b <= a; b++)
System.out.print ("* ");
System.out.println();
}
num-=1;
for (int a = 0; a<=num; a++) {
for (int b = num; b > a; b--)
System.out.print (" *");
System.out.println();
for (int c = 0; c <= e; c++)
System.out.print(" ");
e+=1;
}
}
}