A sample utility class with a few methods for testing

Utility.java

package com.diffblue.demo;

import org.springframework.util.Assert;

/**
 * The following methods are used to automatically generate unit test for.
 */
public class Utility {
	enum Color {
		RED,
		YELLOW,
		BLUE
	}

	public static int sum(int arg1, int arg2) {
		return arg1 + arg2;
	}

	public static double divide(int divide, int divideBy) {
		if (divideBy == 0) {
			throw new RuntimeException("This operation would result in division by zero error.");
		}

		return divide / divideBy;
	}

	public static boolean isColorSupported(Color color) {
		Assert.isTrue(color != null, "color cannot be null");

		switch (color) {
			case RED:
			/* fallthrough */
			case YELLOW:
			case BLUE: return true;
		}

		return false;
	}

	public static long calculateFactorial(int num) {
		if (num >= 1) {
			return num * calculateFactorial(num - 1);
		}
		else {
			return 1;
		}
	}

	public static boolean isPrime(int n, int i) {
		if (n <= 2) {
			return (n == 2) ? true : false;
		}
		if (n % i == 0) {
			return false;
		}
		if (i * i > n) {
			return true;
		}

		return isPrime(n, i + 1);
	}

	public static boolean isEven(int n) {
		if (n % 2 == 0) {
			return true;
		}

		return false;
	}
}