package Maths; /** Find the area of various geometric shapes */ public class Area { public static void main(String[] args) { /* test cube */ assert Double.compare(surfaceAreaCube(1), 6.0) == 0; /* test sphere */ assert Double.compare(surfaceAreaSphere(5), 314.1592653589793) == 0; assert Double.compare(surfaceAreaSphere(1), 12.566370614359172) == 0; /* test rectangle */ assert Double.compare(surfaceAreaRectangle(10, 20), 200.0) == 0; /* test square */ assert Double.compare(surfaceAreaSquare(10), 100.0) == 0; /* test triangle */ assert Double.compare(surfaceAreaTriangle(10, 10), 50.0) == 0; /* test parallelogram */ assert Double.compare(surfaceAreaParallelogram(10, 20), 200.0) == 0; /* test trapezium */ assert Double.compare(surfaceAreaTrapezium(10, 20, 30), 450.0) == 0; /* test circle */ assert Double.compare(surfaceAreaCircle(20), 1256.6370614359173) == 0; } /** * Calculate the surface area of a cube. * * @param sideLength side length of cube * @return surface area of given cube */ private static double surfaceAreaCube(double sideLength) { return 6 * sideLength * sideLength; } /** * Calculate the surface area of a sphere. * * @param radius radius of sphere * @return surface area of given sphere */ private static double surfaceAreaSphere(double radius) { return 4 * Math.PI * radius * radius; } /** * Calculate the area of a rectangle * * @param length length of rectangle * @param width width of rectangle * @return area of given rectangle */ private static double surfaceAreaRectangle(double length, double width) { return length * width; } /** * Calculate the area of a square * * @param sideLength side length of square * @return area of given square */ private static double surfaceAreaSquare(double sideLength) { return sideLength * sideLength; } /** * Calculate the area of a triangle * * @param base base of triangle * @param height height of triangle * @return area of given triangle */ private static double surfaceAreaTriangle(double base, double height) { return base * height / 2; } /** * Calculate the area of a parallelogram * * @param base base of parallelogram * @param height height of parallelogram * @return area of given parallelogram */ private static double surfaceAreaParallelogram(double base, double height) { return base * height; } /** * Calculate the area of a trapezium * * @param base1 upper base of trapezium * @param base2 bottom base of trapezium * @param height height of trapezium * @return area of given trapezium */ private static double surfaceAreaTrapezium(double base1, double base2, double height) { return (base1 + base2) * height / 2; } /** * Calculate the area of a circle * * @param radius radius of circle * @return area of given circle */ private static double surfaceAreaCircle(double radius) { return Math.PI * radius * radius; } }