HomeWork3
Homework3
7.Using the following method printPrimes() for questions a-d below
/*******************************************************
* Finds and prints n prime integers
* Jeff Offutt, Spring 2003
******************************************************/
public static void printPrimes (int n)
{
int curPrime; // Value currently considered for primeness
int numPrimes; // Number of primes found so far.
boolean isPrime; // Is curPrime prime?
int [] primes = new int [MAXPRIMES]; // The list of prime numbers.
// Initialize 2 into the list of primes.
primes [0] = 2;
numPrimes = 1;
curPrime = 2;
while (numPrimes < n)
{
curPrime++; // next number to consider ...
isPrime = true;
for (int i = 0; i <= numPrimes-1; i++)
{ // for each previous prime.
if (curPrime%primes[i]==0)
{ // Found a divisor, curPrime is not prime.
isPrime = false;
break; // out of loop through primes.
}
}
if (isPrime)
{ // save it!
primes[numPrimes] = curPrime;
numPrimes++;
}
} // End while
// Print all the primes out.
for (int i = 0; i <= numPrimes-1; i++)
{
System.out.println ("Prime: " + primes[i]);
}
} // end printPrimes
a) Draw the control flow graph for the printPrimes() method.
Answer：
(b) Consider test cases t1=(n=3) and t2=(n=5). Although these tour the same prime paths in ptinrPrimes(), they do not necessarily find the same faults. Design a simple fault that t2 would be more likely to discover than t1 would.
Answer：
当MAXPRIMES = 3 、4时, t2=(n=5) 会溢出 ，t1=(n=3) 不会溢出。
(c) For printPrimes(), find a test case such that the corresponding test path visits the edge that connects the beginning of the while statement to the for statement withtout going through the body of the while loop.
Answer：
当n=1的时候，测试用例会通过边对（2，12）。
(d) Enumerate the test requirements for node coverage, edge coverage, amd prime path coverage for the graph fpr printPrime().
Answer：
1) Node Coverage
TR = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16};
2) Edge Coverage
TR = {(1,2), (2,3), (2,12), (3,4), (4,5), (5,6), (5,9), (6,7), (6,8), (7,5), (8,9)
(9,10), (9,11), (10,11), (11,2), (12,13), (13,14), (13,16), (14,15), (15,13)};
3) Prime Path Coverage
TR = {[1,2,3,4,5,6,7], [1,2,3,4,5,6,8,9,10,11], [1,2,3,4,5,6,8,9,11], [1,2,3,4,5,9,10,11],
[1,2,12,13,14,15], [1,2,12,13,16],
[2,3,4,5,6,8,9,10,11,2], [3,4,5,6,8,9,10,11,2,3], [4,5,6,8,9,10,11,2,3,4], [5,6,8,9,10,11,2,3,4,5],
[6,8,9,10,11,2,3,4,5,6], [8,9,10,11,2,3,4,5,6,8], [9,10,11,2,3,4,5,6,8,9], [10,11,2,3,4,5,6,8,9,10],
[11,2,3,4,5,6,8,9,10,11],
[2,3,4,5,6,8,9,11,2], [3,4,5,6,8,9,11,2,3], [4,5,6,8,9,11,2,3,4], [5,6,8,9,11,2,3,4,5],
[6,8,9,11,2,3,4,5,6], [8,9,11,2,3,4,5,6,8], [9,11,2,3,4,5,6,8,9], [11,2,3,4,5,6,8,9,11],
[2,3,4,5,9,10,11,2], [3,4,5,9,10,11,2,3], [4,5,9,10,11,2,3,4], [5,9,10,11,2,3,4,5],
[9,10,11,2,3,4,5,9], [10,11,2,3,4,5,9,10], [11,2,3,4,5,9,10,11],
[2,3,4,5,9,11,2], [3,4,5,9,11,2,3], [4,5,9,11,2,3,4], [5,9,11,2,3,4,5], [9,11,2,3,4,5,9],
[11,2,3,4,5,9,11],
[13,14,15,13], [14,15,13,14], [15,13,14,15],
[5,6,7,5], [6,7,5,6], [7,5,6,7],
[3,4,5,9,11,2,12,13,16], [3,4,5,9,10,11,2,12,13,16], [3,4,5,6,8,9,11,2,12,13,16],
[3,4,5,6,8,9,10,11,2,12,13,16],
[3,4,5,9,11,2,12,13,14,15], [3,4,5,9,10,11,2,12,13,14,15], [3,4,5,6,8,9,11,2,12,13,14,15],
[3,4,5,6,8,9,10,11,2,12,13,14,15],
[6,7,5,9,11,2,3,4], [6,7,5,9,10,11,2,3,4], [6,7,5,9,11,2,12,13,14,15], [6,7,5,9,10,11,2,12,13,14,15],
[6,7,5,9,11,2,12,13,16], [6,7,5,9,10,11,2,12,13,16],
[7,5,6,8,9,11,2,3,4], [7,5,6,8,9,10,11,2,3,4], [7,5,6,8,9,11,2,12,13,14,15],
[7,5,6,8,9,10,11,2,12,13,14,15], [7,5,6,8,9,11,2,12,13,16], [7,5,6,8,9,10,11,2,12,13,16],
[8,9,11,2,3,4,5,6,7], [8,9,10,11,2,3,4,5,6,7],
[14,15,13,16] };
基于Junit及Eclemma（jacoco）实现一个主路径覆盖的测试。
项目结构：
项目源代码：
PrintPrime.java
1 package cn.tju.hw3; 2 3 public class PrintPrime { 4 5 private static final int MAXPRIMES = 100000000; 6 public static String printPrimes(int n) { 7 String ResultString = ""; 8 int curPrime; // Value currently considered for primeness 9 int numPrimes; // Number of primes found so far. 10 boolean isPrime; // Is curPrime prime? 11 int[] primes = new int[MAXPRIMES]; // The list of prime numbers. 12 13 // Initialize 2 into the list of primes. 14 primes[0] = 2; 15 numPrimes = 1; 16 curPrime = 2; 17 while (numPrimes < n) { 18 curPrime++; // next number to consider ... 19 isPrime = true; 20 for (int i = 0; i <= numPrimes - 1; i++) { // for each previous prime. 21 if (curPrime % primes[i] == 0) { // Found a divisor, curPrime is not prime. 22 isPrime = false; 23 break; // out of loop through primes. 24 } 25 } 26 if (isPrime) { // save it! 27 primes[numPrimes] = curPrime; 28 numPrimes++; 29 } 30 } // End while 31 32 // Print all the primes out. 33 for (int i = 0; i <= numPrimes - 1; i++) { 34 ResultString = ResultString + primes[i] + " "; 35 } 36 return ResultString; 37 } // end printPrimes 38 39 }
PrintPrimeTest.java1 package cn.tju.hw3; 2 3 import static org.junit.Assert.*; 4 import java.util.Collection; 5 6 import org.junit.Before; 7 import org.junit.Test; 8 import org.junit.runner.RunWith; 9 import org.junit.runners.Parameterized; 10 import org.junit.runners.Parameterized.Parameters; 11 import java.util.Arrays; 12 13 @RunWith(Parameterized.class) 14 public class PrintPrimeTest { 15 private String expected = ""; 16 private int n; 17 private PrintPrime pp; 18 19 public PrintPrimeTest(int num, String expec) { 20 n = num; 21 expected = expec; 22 } 23 24 @Before 25 public void setUp() { 26 pp = new PrintPrime(); 27 } 28 29 @Test 30 public void test() { 31 assertEquals(this.expected, pp.printPrimes(this.n)); 32 } 33 34 @Parameters 35 public static Collection<Object[]> getData() { 36 return Arrays.asList(new Object[][] { { 6, "2 3 5 7 11 13 " } }); 37 // return Arrays.asList(new Object[][] {{ 2, "2 3 " } }); 38 } 39 }
运行结果：
