2.java

// Java program to Print Reverse Pyramid Star Pattern
// Using While loop

// Importing input output classes
import java.io.*;

// Main class
class GFG {

	// Main driver method
	public static void main(String[] args)
	{
		// Declaring and initializing variable to
		// Size of the pyramid
		int number = 7;

		int i = number, j;

		// Nested while loops
		// Outer loop

		// Till condition holds true
		while (i > 0) {
			j = 0;

			// Inner loop
			// Condition check
			while (j++ < number - i) {
				// Print whitespaces
				System.out.print(" ");
			}

			j = 0;

			// Inner loop
			// Condition check
			while (j++ < (i * 2) - 1) {
				// Print star
				System.out.print("*");
			}

			// By now, we reach end of execution for one row
			// so next line
			System.out.println();

			// Decrementing counter because we want to print
			// reverse of pyramid
			i--;
		}
	}
}