Star Pattern In Java

Recently i was learning Java programming and while practicing some of the fundamentals i created some star patterns.

Working with pattern program in Java helped me think clearly the flow and working of fundamentals like if-else and loops.

1. Square star pattern

*****
*****
*****
*****
*****

Here is code to create it:

class squarePattern {
  public static void main(String[] args) {

    // size of the square
    int size = 5;
    // outer loop
    for (int i = 0; i < size; i++) {
      // inner loop
      for (int j = 0; j < size; j++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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2. Left triangle star pattern

*
**
***
****
*****

Here is the code to create it.

class leftTrianlge {
  public static void main(String[] args) {

    // size of the triangle
    int size = 5;
    // loop to print the pattern
    for (int i = 0; i < size; i++) {
      // print column
      for (int j = 0; j <= i; j++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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3. Left triangle star pattern

    *
   **
  ***
 ****
*****

Here is the code:

class rightTrianlge {
  public static void main(String[] args) {

    // size of the triangle
    int size = 5;
    // loop to print the pattern
    for (int i = 0; i < size; i++) {
      // print spaces
      for (int j = 1; j < size - i; j++) {
        System.out.print(" ");
      }
      // print stars
      for (int k = 0; k <= i; k++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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4. Pyramid star pattern in Java

    *
   ***
  *****
 *******
*********

Here is complete code for this:

class pyramid {
  // pyramid star pattern
  public static void main(String[] args) {

    int size = 5;
    for (int i = 0; i < size; i++) {
      // print spaces
      for (int j = 0; j < size - i - 1; j++) {
        System.out.print(" ");
      }
      // print stars
      for (int k = 0; k < 2 * i + 1; k++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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5. Hollow pyramid pattern

    *
   * *
  *   *
 *     *
*********

Here is complete code:

class hollowPyramid {
  public static void main(String[] args) {
    // size of the pyramid
    int size = 5;
    for (int  i = 0; i < size; i++) {
      // print spaces
      for (int j = 0; j < size - i - 1; j++) {
        System.out.print(" ");
      }
      // print stars
      for (int k = 0; k < 2 * i + 1; k++) {
        if (i == 0 || i == size - 1) {
          System.out.print("*");
        }
        else {
          if (k == 0 || k == 2 * i) {
            System.out.print("*");
          }
          else {
            System.out.print(" ");
          }
        }
      }
      System.out.println();
    }
  }
}

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6. Diamond star pattern

    *
   ***
  *****
 *******
*********
 *******
  *****
   ***
    *

Here is complete code:

class diamond {
  public static void main(String[] args) {
    int size = 5;
    // upside pyramid
    for (int i = 1; i <= size; i++) {
      // printing spaces
      for (int j = size; j > i; j--) {
        System.out.print(" ");
      }
      // printing star
      for (int k = 0; k < i * 2 - 1; k++) {
        System.out.print("*");
      }
      System.out.println();
    }
    // downside pyramid
    for (int i = 1; i <= size - 1; i++) {
      // printing spaces
      for (int j = 0; j < i; j++) {
        System.out.print(" ");
      }
      // printing star
      for (int k = (size - i) * 2 - 1; k > 0; k--) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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7. Hourglass pattern

*********
 *******
  *****
   ***
    *
   ***
  *****
 *******
*********

Here is complete code for this:

class hourGlass {
  public static void main(String[] args) {
    int size = 5;
    // reversed pyramid star pattern
    for (int i = 0; i < size; i++) {
      // printing spaces
      for (int j = 0; j < i; j++) {
        System.out.print(" ");
      }
      // printing star
      for (int k = 0; k < (size - i) * 2 - 1; k++) {
        System.out.print("*");
      }
      System.out.println();
    }
    // pyramid star pattern
    for (int i = 2; i <= size; i++) {
      // printing spaces
      for (int j = size; j > i; j--) {
        System.out.print(" ");
      }
      // printing star
      for (int k = 0; k < i * 2 - 1; k++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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8. Heart pattern

 ***   ***
***** *****
***********
 *********
  *******
   *****
    ***
     *

Here is complete code:

class heart {
  public static void main(String[] args) {
    // heart star pattern
    int size = 6;

    for (int i = size / 2; i < size; i += 2) {
      // print first spaces
      for (int j = 1; j < size - i; j += 2) {
        System.out.print(" ");
      }
      // print first stars
      for (int j = 1; j < i + 1; j++) {
        System.out.print("*");
      }
      // print second spaces
      for (int j = 1; j < size - i + 1; j++) {
        System.out.print(" ");
      }
      // print second stars
      for (int j = 1; j < i + 1; j++) {
        System.out.print("*");
      }
      System.out.println();
    }
    // lower part
    // inverted pyramid
    for (int i = size; i > 0; i--) {
      for (int j = 0; j < size - i; j++) {
        System.out.print(" ");
      }
      for (int j = 1; j < i * 2; j++) {
        System.out.print("*");
      }
      System.out.println();
    }
  }
}

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Reference: TutorialsTonight.com