Write a Java Program to print hollow diamond pattern inside a square star pattern using a while loop. Here, we used multiple while loop and if-else statements to print the hollow diamond pattern printed inside a square pattern.
package ShapePrograms;
import java.util.Scanner;
public class HollowDiamondinsideSquare1 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
int i, j, k;
System.out.print("Enter Hollow Diamond inside a Square Rows = ");
int rows = sc.nextInt();
System.out.println("Printing Hollow Diamond Star Pattern inside a Square");
i = 0 ;
while( i < rows)
{
j = 0 ;
while ( j < rows )
{
if(j < rows - i) {
System.out.print("*");
}
else {
System.out.print(" ");
}
j++;
}
k = 0 ;
while ( k < rows)
{
if (k < i ) {
System.out.print(" ");
}
else {
System.out.print("*");
}
k++ ;
}
System.out.println();
i++;
}
i = 1 ;
while ( i <= rows )
{
j = 0 ;
while ( j < rows )
{
if(j < i) {
System.out.print("*");
}
else {
System.out.print(" ");
}
j++;
}
k = 0 ;
while ( k < rows)
{
if (k < rows - i ) {
System.out.print(" ");
}
else {
System.out.print("*");
}
k++ ;
}
System.out.println();
i++;
}
}
}
Enter Hollow Diamond inside a Square Rows = 8
Printing Hollow Diamond Star Pattern inside a Square
****************
******* *******
****** ******
***** *****
**** ****
*** ***
** **
* *
* *
** **
*** ***
**** ****
***** *****
****** ******
******* *******
****************
In this Java hollow diamond star pattern inside a square program, we alter the above code to remove all the if-else statements.
package ShapePrograms;
import java.util.Scanner;
public class HollowDiamondinsideSquare2 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
int i, j, k;
System.out.print("Enter Hollow Diamond inside a Square Rows = ");
int rows = sc.nextInt();
System.out.println("Printing Hollow Diamond Star Pattern inside a Square");
for (i = 1 ; i <= rows; i++ )
{
for (j = i ; j <= rows; j++ )
{
System.out.print("*");
}
for (j = 1 ; j <= 2 * i - 2; j++ )
{
System.out.print(" ");
}
for (k = i ; k <= rows; k++ )
{
System.out.print("*");
}
System.out.println();
}
for (i = 1 ; i <= rows; i++ )
{
for (j = 1 ; j <= i; j++ )
{
System.out.print("*");
}
for (k = 2 * i - 2 ; k < 2 * rows - 2; k++ )
{
System.out.print(" ");
}
for (k = 1 ; k <= i; k++ )
{
System.out.print("*");
}
System.out.println();
}
}
}

This hollow diamond Pattern inside a square program is the same as the first example, and we replaced the while loop with for loop.
package ShapePrograms;
import java.util.Scanner;
public class HollowDiamondinsideSquare3 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
int i, j, k;
System.out.print("Enter Hollow Diamond inside a Square Rows = ");
int rows = sc.nextInt();
System.out.println("Printing Hollow Diamond Star Pattern inside a Square");
for (i = 0 ; i < rows; i++ )
{
for (j = 0 ; j < rows; j++ )
{
if(j < rows - i) {
System.out.print("*");
}
else {
System.out.print(" ");
}
}
for (k = 0 ; k < rows; k++ )
{
if (k < i ) {
System.out.print(" ");
}
else {
System.out.print("*");
}
}
System.out.println();
}
for (i = 1 ; i <= rows; i++ )
{
for (j = 0 ; j < rows; j++ )
{
if(j < i) {
System.out.print("*");
}
else {
System.out.print(" ");
}
}
for (k = 0 ; k < rows; k++ )
{
if (k < rows - i ) {
System.out.print(" ");
}
else {
System.out.print("*");
}
}
System.out.println();
}
}
}
Enter Hollow Diamond inside a Square Rows = 12
Printing Hollow Diamond Star Pattern inside a Square
************************
*********** ***********
********** **********
********* *********
******** ********
******* *******
****** ******
***** *****
**** ****
*** ***
** **
* *
* *
** **
*** ***
**** ****
***** *****
****** ******
******* *******
******** ********
********* *********
********** **********
*********** ***********
************************