【软件测试】（homework3）覆盖问题

使用方法printPrimes()完成（a）~（f）题：

代码如下：

 1 /******************************************************* 
 2      * Finds and prints n prime integers 
 3      * Jeff Offutt, Spring 2003 
 4      ******************************************************/ 
 5     public static void printPrimes (int n) 
 6     { 
 7         int curPrime; // Value currently considered for primeness 
 8         int numPrimes; // Number of primes found so far. 
 9         boolean isPrime; // Is curPrime prime? 
10         int [] primes = new int [MAXPRIMES]; // The list of prime numbers. 
11         
12         // Initialize 2 into the list of primes. 
13         primes [0] = 2; 
14         numPrimes = 1; 
15         curPrime = 2; 
16         while (numPrimes < n) 
17         { 
18             curPrime++; // next number to consider ... 
19             isPrime = true; 
20             for (int i = 0; i <= numPrimes-1; i++) 
21             { // for each previous prime. 
22                 if (isDivisible(primes[i], curPrime)) 
23                 { // Found a divisor, curPrime is not prime. 
24                     isPrime = false; 
25                     break; // out of loop through primes. 
26                 } 
27             } 
28             if (isPrime) 
29             { // save it! 
30                 primes[numPrimes] = curPrime; 
31                 numPrimes++; 
32             } 
33         } // End while 
34         
35         // Print all the primes out. 
36         for (int i = 0; i <= numPrimes-1; i++) 
37         { 
38             System.out.println ("Prime: " + primes[i]); 
39         } 
40     } // end printPrimes

(a) 控制流图：

(b) 考虑测试用例 t1=(n=3) 和 t2=(n=5)，当一个错误是数组越界错误时，t2比t1更容易发现错误。

(d)

节点覆盖：{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}

边覆盖：{(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),(14,15),(15,13),(13,16)}

主路经覆盖：

{(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),

(1,2,3,4,5,9,11),

(1,2,12,13,14,15),

(1,2,12,13,16),

(2,3,4,5,6,8,9,10,11,2),

(2,3,4,5,6,8,9,11,2),

(2,3,4,5,9,10,11,2),

(2,3,4,5,9,11,2),

(3,4,5,6,8,9,10,11,2,12,13,14,15),

(3,4,5,6,8,9,11,2,12,13,14,15)

(3,4,5,6,8,9,10,11,2,12,13,16)

(3,4,5,6,8,9,11,2,12,13,16),

(3,4,5,9,10,11,2,12,13,14,15),

(3,4,5,9,11,2,12,13,14,15),

(3,4,5,9,10,11,2,12,13,16),

(3,4,5,9,11,2,12,13,16),

(5,6,7,5),

(6,7,5,9,10,11,2,12,13,14,15),

(6,7,5,9,11,2,12,13,14,15),

(6,7,5,9,10,11,2,12,13,16),

(6,7,5,9,11,2,12,13,16),

(14,15,13,16),

(13,14,15,13),}

*实现主路经覆盖的例子：