Answer to Question #200567 in Software Engineering for AWAIS

Question

Exercise 1:

 

1.     //The max function the max between a and b, it returns a if a == //b

public double max(double a, double b);  

 

2.     //The mult function returns the result of a * b public double mult(double a, double b);

 

3.     //The exist in array function returns the index of the element //‘a’ if //‘a’ exist in array ‘arr’ otherwise returns ‘-1’ public int existsInArray(int [] arr, int a);

 

4.     //Are array equals method compares two arrays and returns true // if the elements of array ‘a’ are equal to elements of array

// ‘b’, element by element. If equals it returns 0, it returns -

// 1 if not

public int areArrayEquals(int [] a, int [] b); 

 

 

Devise four executable test cases for every method in the JUnit notation. See the attached handout for a refresher on the notation.  

Answer 1

import static org.junit.Assert.*;
import org.junit.*;


class Function {
	/**
	 * The max function the max between a and b, it returns a if a == //b
	 * 
	 * @param a
	 * @param b
	 * @return
	 */
	public double max(double a, double b) {
		if (a >= b) {
			return a;
		}
		return b;
	}


	/**
	 * The mult function returns the result of a * b
	 * 
	 * @param a
	 * @param b
	 * @return
	 */
	public double mult(double a, double b) {
		return a * b;
	}


	/**
	 * The exist in array function returns the index of the element //‘a’ if //‘a’
	 * exist in array ‘arr’ otherwise returns ‘-1’
	 * 
	 * @param arr
	 * @param a
	 * @return
	 */
	public int existsInArray(int[] arr, int a) {
		for (int i = 0; i < arr.length; i++) {
			if (arr[i] == a) {
				return i;
			}
		}
		return -1;
	}


	/***
	 * Are array equals method compares two arrays and returns true // if the
	 * elements of array ‘a’ are equal to elements of array ‘b’, element by element.
	 * If equals it returns 0, it returns - 1 if not
	 * 
	 * @param a
	 * @param b
	 * @return
	 */
	public int areArrayEquals(int[] a, int[] b) {
		if (a.length <= b.length) {
			return -1;
		}
		for (int i = 0; i < a.length; i++) {
			if (a[i] != b[i]) {
				return -1;
			}
		}
		return 0;
	}
}


public class JFunctionsTest {
	private Function function;
    
     
    @Before
    public void setUp() {
    	function=new Function();
    }
     
	@Test
    public void testMax() {
    	double a = 25.0;
    	double b = 56.0;
    	double actual = function.max(a, b);
    	double expected = 56.0;
    	assertTrue(expected==actual);
    }
	@Test
    public void testMult() {
    	double a = 2.0;
    	double b = 10.0;
    	double actual = function.mult(a, b);
    	double expected = 20.0;
    	assertTrue(expected==actual);
    }
	@Test
    public void testExistsInArray() {
    	int a = 2;
    	int array[] = { 10,2,56,36,95};
    	int actual = function.existsInArray(array, a);
    	int expected =1;
    	assertTrue(expected==actual);
    }
	@Test
    public void testAreArrayEquals() {
		int a[] = { 10,2,56,36,95};
		int b[] = { 14,2,56,36,95};
		int actual = function.areArrayEquals(a, b);
		int expected =-1;
    	assertTrue(expected==actual);
    }
}