Write a Java Program to print a diamond star pattern using for loop. The Diamond pattern is a combination of a pyramid and an inverted pyramid. So, this star diamond example divides code to print the normal and inverted pyramid.
package ShapePrograms; import java.util.Scanner; public class DiamondPattern1 { private static Scanner sc; public static void main(String[] args) { sc = new Scanner(System.in); int i, j; System.out.print("Enter Diamond Pattern Rows = "); int rows = sc.nextInt(); System.out.println("Printing Diamond Star Pattern"); for (i = 1 ; i <= rows; i++ ) { for (j = 1 ; j <= rows - i; j++ ) { System.out.print(" "); } for (j = 1 ; j <= i * 2 - 1; j++ ) { System.out.print("*"); } System.out.println(); } for (i = rows - 1 ; i > 0; i-- ) { for (j = 1 ; j <= rows - i; j++ ) { System.out.print(" "); } for (j = 1 ; j <= i * 2 - 1; j++ ) { System.out.print("*"); } System.out.println(); } } }

Java Program to Print Diamond Star Pattern using while loop
In this Diamond Pattern of stars program, we replaced the for loop with a while loop.
package ShapePrograms; import java.util.Scanner; public class DiamondPattern3 { private static Scanner sc; public static void main(String[] args) { sc = new Scanner(System.in); int i, j, k; System.out.print("Enter Diamond Pattern Rows = "); int rows = sc.nextInt(); System.out.println("Printing Diamond Star Pattern"); i = 1 ; while(i <= rows ) { j = 1 ; while( j <= rows - i ) { System.out.print(" "); j++; } k = 1 ; while ( k <= i * 2 - 1 ) { System.out.print("*"); k++; } System.out.println(); i++; } i = rows - 1 ; while( i > 0 ) { j = 1 ; while ( j <= rows - i ) { System.out.print(" "); j++; } k = 1 ; while( k <= i * 2 - 1 ) { System.out.print("*"); k++; } System.out.println(); i--; } } }
Enter Diamond Pattern Rows = 12
Printing Diamond Star Pattern
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Java Program to Print Diamond Star Pattern using do while loop
package ShapePrograms; import java.util.Scanner; public class DiamondPattern4 { private static Scanner sc; public static void main(String[] args) { sc = new Scanner(System.in); int i, j, k; System.out.print("Enter Diamond Pattern Rows = "); int rows = sc.nextInt(); System.out.println("Printing Diamond Star Pattern"); i = 1 ; do { j = 1 ; do { System.out.print(" "); } while( j++ <= rows - i ) ; k = 1 ; do { System.out.print("*"); } while ( ++k <= i * 2 - 1 ) ; System.out.println(); } while(++i <= rows ) ; i = rows - 1 ; do { j = 1 ; do { System.out.print(" "); } while (j++ <= rows - i ) ; k = 1 ; do { System.out.print("*"); } while( ++k <= i * 2 - 1 ) ; System.out.println(); } while( --i > 0 ) ; } }
Enter Diamond Pattern Rows = 15
Printing Diamond Star Pattern
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In this example, the diamondPattern function prints the diamond pattern of a given symbol.
package ShapePrograms; import java.util.Scanner; public class DiamondPattern2 { private static Scanner sc; public static void main(String[] args) { sc = new Scanner(System.in); System.out.print("Enter Diamond Pattern Rows = "); int rows = sc.nextInt(); System.out.print("Enter Character for Diamond Pattern = "); char ch = sc.next().charAt(0); diamondPattern(rows, ch); } public static void diamondPattern(int rows, char ch) { int i, j, k; int x = rows - 1; int y = 1; for (i = 1 ; i <= rows; i++ ) { for (j = 1 ; j <= x; j++ ) { System.out.print(" "); } for (k = 1 ; k <= y; k++ ) { System.out.print(ch); } if(x > i) { x = x - 1; y = y + 2; } if(x < i) { x = x + 1; y = y - 2; } System.out.println(); } } }
Enter Diamond Pattern Rows = 10
Enter Character for Diamond Pattern = #
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