Java Hollow diamond star pattern program

Table of Contents

Java Hollow diamond star pattern program

In this article, we will discuss the Java Hollow diamond star pattern program – using loops

In this post, we will learn how to create a hollow diamond star pattern using for, while and do-wile loop in Java language

Diamond star pattern using for loop

Program 1

This program allows the user to enter the number of rows and the symbol then the program displays the hollow diamond star pattern with the given symbol using for loop in java language

import java.util.Scanner;
class HollowDiamondPattern{
public static void main(String args[]){
int i,j;
Scanner scan=new Scanner(System.in);
System.out.print("Enter the number of rows");
int rows=scan.nextInt();
System.out.println("Enter symbol as you wish: "); 
char ch=scan.next().charAt(0);
//read number input from user


for(i=1; i<=rows; i++){
    for(j=rows; j>i; j--){
     System.out.print(" ");
  }
  System.out.print(ch);
  for(j=1; j<(i-1)*2; j++){
     System.out.print(" ");
  }
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
}
  
for(i=rows-1; i>=1; i--){
    for(j=rows; j>i; j--){
     System.out.print(" ");
  }
  System.out.print(ch);
  for(j=1; j<(i-1)*2; j++){
     System.out.print(" ");
  }
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
  }
  }
  }

When the above code is executed. it produces the following result

Java Hollow diamond star pattern program — Diamond pattern program

Diamond star pattern using the while loop

Program 2

This program allows the user to enter the number of rows and the symbol then the program displays the hollow diamond star pattern with the given symbol using while loop in java language

import java.util.Scanner;
class HollowDiamondwhile{
public static void main(String args[]){
int i,j;
Scanner scan=new Scanner(System.in);
System.out.print("Enter the number of rows: ");

int rows=scan.nextInt();
System.out.println("Enter symbol as you wish: "); 
char ch=scan.next().charAt(0);
i=1;
while(i<=rows){
  j=rows;
    while(j>i){
     System.out.print(" ");
     j--;
  }
  System.out.print(ch);
  j=1;
  while(j<(i-1)*2){
     System.out.print(" ");
     j++;
  }
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
   i++;
}
  i=rows-1;
while( i>=1){
  j=rows;
    while(j>i){
     System.out.print(" ");
      j--;
  }
  System.out.print(ch);
  j=1;
  while(j<(i-1)*2){
     System.out.print(" ");
      j++;
  }
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
   i--;
  }
  }
  }

When the above code is executed. it produces the following result

Diamond star pattern using the do-while loop

Program 3

This program allows the user to enter the number of rows and the symbol then the program displays the hollow diamond star pattern with the given symbol using do-while loop in Java language

import java.util.Scanner;
class HollowDiamonddowhile{
public static void main(String args[]){
int i,j;
Scanner scan=new Scanner(System.in);
System.out.print("Enter the number of rows: ");

int rows=scan.nextInt();
System.out.println("Enter symbol as you wish: "); 
char ch=scan.next().charAt(0);
i=1;
do{
  j=rows;
   do{
     System.out.print(" ");
     j--;
  } while(j>=i);
  System.out.print(ch);
  j=1;
  do{
     System.out.print(" ");
     j++;
  }while(j<(i-1)*2);
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
   i++;
}while(i<=rows);
  i=rows-1;
do{
  j=rows;
    do{
     System.out.print(" ");
      j--;
  }while(j>=i);
  System.out.print(ch);
  j=1;
  do{
     System.out.print(" ");
      j++;
  }while(j<(i-1)*2);
  if(i==1){
    System.out.print("\n");
  }
  else{
    System.out.print(ch+"\n");
  }
   i--;
  }while( i>=1);
  }
  }

When the above code is executed. it produces the following result