Area.java

package com.thealgorithms.maths;

/**
 * Find the area of various geometric shapes
 */
public final class Area {
 private Area() {
 }

 /**
 * String of IllegalArgumentException for radius
 */
 private static final String POSITIVE_RADIUS = "Radius must be greater than 0";

 /**
 * String of IllegalArgumentException for height
 */
 private static final String POSITIVE_HEIGHT = "Height must be greater than 0";

 /**
 * String of IllegalArgumentException for base
 */
 private static final String POSITIVE_BASE = "Base must be greater than 0";

 /**
 * Calculate the surface area of a cube.
 *
 * @param sideLength side length of cube
 * @return surface area of given cube
 */
 public static double surfaceAreaCube(final double sideLength) {
 if (sideLength <= 0) {
 throw new IllegalArgumentException("Side length must be greater than 0");
 }
 return 6 * sideLength * sideLength;
 }

 /**
 * Calculate the surface area of a cuboid.
 *
 * @param length length of the cuboid
 * @param width width of the cuboid
 * @param height height of the cuboid
 * @return surface area of given cuboid
 */
 public static double surfaceAreaCuboid(final double length, double width, double height) {
 if (length <= 0) {
 throw new IllegalArgumentException("Length must be greater than 0");
 }
 if (width <= 0) {
 throw new IllegalArgumentException("Width must be greater than 0");
 }
 if (height <= 0) {
 throw new IllegalArgumentException("Height must be greater than 0");
 }
 return 2 * (length * width + length * height + width * height);
 }

 /**
 * Calculate the surface area of a sphere.
 *
 * @param radius radius of sphere
 * @return surface area of given sphere
 */
 public static double surfaceAreaSphere(final double radius) {
 if (radius <= 0) {
 throw new IllegalArgumentException(POSITIVE_RADIUS);
 }
 return 4 * Math.PI * radius * radius;
 }

 /**
 * Calculate the surface area of a pyramid with a square base.
 *
 * @param sideLength side length of the square base
 * @param slantHeight slant height of the pyramid
 * @return surface area of the given pyramid
 */
 public static double surfaceAreaPyramid(final double sideLength, final double slantHeight) {
 if (sideLength <= 0) {
 throw new IllegalArgumentException("");
 }
 if (slantHeight <= 0) {
 throw new IllegalArgumentException("slant height must be greater than 0");
 }
 double baseArea = sideLength * sideLength;
 double lateralSurfaceArea = 2 * sideLength * slantHeight;
 return baseArea + lateralSurfaceArea;
 }

 /**
 * Calculate the area of a rectangle.
 *
 * @param length length of a rectangle
 * @param width width of a rectangle
 * @return area of given rectangle
 */
 public static double surfaceAreaRectangle(final double length, final double width) {
 if (length <= 0) {
 throw new IllegalArgumentException("Length must be greater than 0");
 }
 if (width <= 0) {
 throw new IllegalArgumentException("Width must be greater than 0");
 }
 return length * width;
 }

 /**
 * Calculate surface area of a cylinder.
 *
 * @param radius radius of the floor
 * @param height height of the cylinder.
 * @return volume of given cylinder
 */
 public static double surfaceAreaCylinder(final double radius, final double height) {
 if (radius <= 0) {
 throw new IllegalArgumentException(POSITIVE_RADIUS);
 }
 if (height <= 0) {
 throw new IllegalArgumentException(POSITIVE_HEIGHT);
 }
 return 2 * (Math.PI * radius * radius + Math.PI * radius * height);
 }

 /**
 * Calculate the area of a square.
 *
 * @param sideLength side length of square
 * @return area of given square
 */
 public static double surfaceAreaSquare(final double sideLength) {
 if (sideLength <= 0) {
 throw new IllegalArgumentException("Side Length must be greater than 0");
 }
 return sideLength * sideLength;
 }

 /**
 * Calculate the area of a triangle.
 *
 * @param base base of triangle
 * @param height height of triangle
 * @return area of given triangle
 */
 public static double surfaceAreaTriangle(final double baseLength, final double height) {
 if (baseLength <= 0) {
 throw new IllegalArgumentException(POSITIVE_BASE);
 }
 if (height <= 0) {
 throw new IllegalArgumentException(POSITIVE_HEIGHT);
 }
 return baseLength * height / 2;
 }

 /**
 * Calculate the area of a parallelogram.
 *
 * @param base base of a parallelogram
 * @param height height of a parallelogram
 * @return area of given parallelogram
 */
 public static double surfaceAreaParallelogram(final double baseLength, final double height) {
 if (baseLength <= 0) {
 throw new IllegalArgumentException(POSITIVE_BASE);
 }
 if (height <= 0) {
 throw new IllegalArgumentException(POSITIVE_HEIGHT);
 }
 return baseLength * 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
 */
 public static double surfaceAreaTrapezium(final double baseLength1, final double baseLength2, final double height) {
 if (baseLength1 <= 0) {
 throw new IllegalArgumentException(POSITIVE_BASE + 1);
 }
 if (baseLength2 <= 0) {
 throw new IllegalArgumentException(POSITIVE_BASE + 2);
 }
 if (height <= 0) {
 throw new IllegalArgumentException(POSITIVE_HEIGHT);
 }
 return (baseLength1 + baseLength2) * height / 2;
 }

 /**
 * Calculate the area of a circle.
 *
 * @param radius radius of circle
 * @return area of given circle
 */
 public static double surfaceAreaCircle(final double radius) {
 if (radius <= 0) {
 throw new IllegalArgumentException(POSITIVE_RADIUS);
 }
 return Math.PI * radius * radius;
 }

 /**
 * Calculate the surface area of a hemisphere.
 *
 * @param radius radius of hemisphere
 * @return surface area of given hemisphere
 */
 public static double surfaceAreaHemisphere(final double radius) {
 if (radius <= 0) {
 throw new IllegalArgumentException(POSITIVE_RADIUS);
 }
 return 3 * Math.PI * radius * radius;
 }

 /**
 * Calculate the surface area of a cone.
 *
 * @param radius radius of cone.
 * @param height of cone.
 * @return surface area of given cone.
 */
 public static double surfaceAreaCone(final double radius, final double height) {
 if (radius <= 0) {
 throw new IllegalArgumentException(POSITIVE_RADIUS);
 }
 if (height <= 0) {
 throw new IllegalArgumentException(POSITIVE_HEIGHT);
 }
 return Math.PI * radius * (radius + Math.pow(height * height + radius * radius, 0.5));
 }
}