點覆蓋：即對程序的控制流圖節點進行全面覆蓋。
邊覆蓋：設計一條路徑，使程序的控制流圖中所有邊被覆蓋。
主路徑覆蓋：就是對程序設計測試用例，使測試用例盡可能多的經過控制流圖中的邊同時不形成環。
習題：
對以下代碼進行分析：
package com.prime;
public class Prime {
public static Boolean isDivisable(int prime, int curPrime) {
if (curPrime % prime == 0) {
return true;
} else
return false;
}
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[100]; // 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 (isDivisable(primes[i], curPrime)) { // 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
}
問題a:畫出程序的控制流圖
問題b:設計一個錯誤，使測試用例t2(n=5)比t1(n=3)更容易發現的錯誤。
將程序中n換成4，這樣測試用例n=3不能發現這個錯誤而n=5能發現。
問題c:測試用例 t(n=1)
問題d:
點覆蓋：[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]
邊覆蓋：[(1,2),(2,3),(3,4),(4,5),(5,6),(6,7),(7,5),(6,8),(8,9),(5,9),(9,10),(10,11),(11,2),(2,12),(12,13),(13,14),(14,15),(15,13),(13,16)]
主路徑覆蓋：
[1,2,3,4,5,6,7]
[1,2,3,4,5,9,10,11]
[1,2,3,4,5,9,11]
[1,2,3,4,5,6,8,9,10,11]
[1,2,3,4,5,6,8,9,11]
[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]
[3,4,5,6,8,9,10,11,2,12,13,16]
[3,4,5,6,8,9,11,2,12,13,14,15]
[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]
[13,14,15,13]
[14,15,13,16]
設計測試代碼如下：
package Primay;
import static org.junit.Assert.*;
import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import org.*;
import org.junit.After;
import org.junit.Before;
import org.junit.Ignore;
import org.junit.Test;
//import org.junit.internal.runners.TestClassRunner;
import org.junit.runner.RunWith;
import Primay.Primaies;
public class PrimaiesTest {
public static Primaies primay = new Primaies();
@Before
public void Start() throws Exception{
primay.Start();
}
@After
public void End() throws Exception{
}
@Test
public void TestNormal(){
String str=new String("Prime: 2\r\nPrime: 3\r\nPrime: 5\r\nPrime: 7\r\nPrime: 11\r\n");
primay.printPrimes(5);
assertEquals(str,primay.Getstr());
}
}
設計時將源代碼輸出到控制台改變為輸出到Primaies類中一個私有成員變量，String類型，每次測試對此變量初始化。
然后測試比較成員變量中與預測結果是否一致。
具體代碼上傳至git中TestJunit項目中:https://github.com/klkjjhjkhjhg/junit
效果圖如下：
程序代碼率：
由於本項目中含有其他文件，所以代碼率不是100%