Junit的简单使用

1 实验

刚学了下利用进行Junit的单元测试，现在来记录下。

JUnit是一个开源的Java编程语言的单元测试框架，应用Junit可以快速高效的对代码进行测试。

现在主要利用JUnit测试如下代码，代码比较简单就不注释了，可以看出代码主要分为两个类BankAccount 和BankAccountGold

 1 public class BankAccount
 2 {
 3     String AccountNumber;
 4     String AccountName;
 5     String ID;
 6     String Password;
 7     double TotalMoney;
 8  
 9     public BankAccount(String AccountNumber, String AccountName, String ID, String Password)
10     {
11         this.AccountNumber = AccountNumber;
12         this.AccountName = AccountName;
13         this.ID = ID;
14         this.Password = Password;      
15     }
16      
17     public void Balance(String AccountNumber)
18     {
19             System.out.println("PLEASE FIND YOUR BALANCE INFORMATION");
20             System.out.println("Account name:" + AccountName);
21             System.out.println("Account number:" + AccountNumber);
22             System.out.println("Your balance:" + TotalMoney);
23     }
24      
25     public void Deposit(double AddMoney)
26     {
27         try
28         {
29             if(AddMoney < 0) throw new RuntimeException();
30             this.TotalMoney += AddMoney;                    
31         }
32         catch(RuntimeException except)
33         {
34             System.out.println("Failed to deposite, money should be larger than 0");
35         }       
36         System.out.println("Deposited money succeeded, the total money is:" + TotalMoney);
37     }
38  
39     public void Withdraw(double GetMoney)
40     {        
41         try
42         {
43             if(GetMoney > this.TotalMoney ) throw new RuntimeException();
44             this.TotalMoney -= GetMoney;
45             System.out.println("You have withdrawed money:" + GetMoney);
46         }
47         catch (RuntimeException except)
48         {
49             System.out.println("Error! you don't have enough balance");
50         }
51     }  
52 }
53  
54 class BankAccountGold extends BankAccount
55 {
56     public BankAccountGold(String AccountNumber, String AccountName, String ID, String Password)
57     {
58         super(AccountNumber,AccountName,ID,Password);   
59     }
60     public void Withdraw(double GetMoney, double overdraft)
61     {
62         overdraft = this.TotalMoney - GetMoney;
63         if(overdraft > 0)
64         {
65             this.TotalMoney = overdraft;
66             System.out.println("Succeeded to withdraw. your balance is" + this.TotalMoney);
67         }
68         else if((overdraft < 0)&&(overdraft > -1000))
69         {
70             this.TotalMoney = overdraft + overdraft * 0.05; // The interest is 5% of the overdraft
71             System.out.println("Succeeded to withdraw. your balance is" + this.TotalMoney);
72         }
73         else
74         {
75             System.out.println("Failed to withdraw, you can not overdraft more than 1000!");
76         }
77     }  
78 }

利用Junit写出的测试代码如下

  1 import static org.junit.Assert.*;
  2 
  3 import org.junit.AfterClass;
  4 import org.junit.Test;
  5 
  6 public class BankAccountTest {
  7 
  8     @AfterClass
  9     public static void tearDownAfterClass() throws Exception {
 10     }
 11 
 12     @Test
 13     public void BankAccount()
 14     {
 15            String AccountNumberTest = new String("1");
 16            String AccountNameTest = new String("Q");
 17            String IDTest = new String("QID");
 18            String PasswordTest = new String("123");
 19            BankAccount s = new BankAccount(AccountNumberTest, AccountNameTest, IDTest, PasswordTest);
 20            assertEquals(AccountNumberTest, s.AccountNumber);
 21            assertEquals(AccountNameTest, s.AccountName);
 22            assertEquals(IDTest, s.ID);
 23            assertEquals(PasswordTest, s.Password);
 24     }
 25     
 26     @Test
 27     public void Balance()
 28     {
 29         BankAccount s = new BankAccount("1", "Q", "QID", "123");
 30         
 31         s.Balance(s.AccountNumber);
 32     }
 33     
 34     @Test
 35     public void ExceptionDeposit() 
 36     {
 37         BankAccount s = new BankAccount("1", "Q", "QID", "123");
 38         s.Deposit(-10);
 39     }
 40     
 41     @Test
 42     public void Deposit()
 43     {
 44         BankAccount s = new BankAccount("1", "Q", "QID", "123");
 45         s.Deposit(10);
 46     }
 47     
 48     @Test
 49     public void ExceptionWithDraw()
 50     {
 51         BankAccount s = new BankAccount("1", "Q", "QID", "123");
 52         s.TotalMoney = 10;
 53         s.Withdraw(100); 
 54     }
 55     
 56     @Test
 57     public void WithDraw()
 58     {
 59         BankAccount s = new BankAccount("1", "Q", "QID", "123");
 60         s.TotalMoney = 100;
 61         s.Withdraw(10);
 62     }
 63 }
 64 
 65 import static org.junit.Assert.*;
 66 
 67 import org.junit.AfterClass;
 68 import org.junit.Test;
 69 
 70 public class BankAccountGoldTest {
 71 
 72     @AfterClass
 73     public static void tearDownAfterClass() throws Exception {
 74     }
 75 
 76     @Test
 77     public void BankAccountGold()
 78     {
 79         String AccountNumberTest = new String("1");
 80         String AccountNameTest = new String("Q");
 81         String IDTest = new String("QID");
 82         String PasswordTest = new String("123");
 83         
 84         BankAccountGold s= new BankAccountGold(AccountNumberTest, AccountNameTest, IDTest, PasswordTest);
 85         assertEquals(AccountNumberTest, s.AccountNumber);
 86         assertEquals(AccountNameTest, s.AccountName);
 87         assertEquals(IDTest, s.ID);
 88         assertEquals(PasswordTest, s.Password);
 89     }
 90     
 91     @Test
 92     public void WithDraw()
 93     {
 94         BankAccountGold s = new BankAccountGold("1", "Q", "QID", "123");
 95         s.TotalMoney = 100;
 96         s.Withdraw(10.0);
 97         s.TotalMoney = 100;
 98         s.Withdraw(150, 0);
 99         s.TotalMoney = 100;
100         s.Withdraw(2000, 0);
101     }
102 }

测试结果如下：

2 总结&问题

　　这是我第一次接触自动的单元测试的框架，感觉还是很新奇。Junit在我看来本质就是利用一些assert等的辅助语句实现对软件自动化测试的工具。刚开始还以为测试用例都可以自己生成，接触后才发现还是无法达到这么智能，需要自己进行书写测试用例，只不过把一些之前可能要利用print才能看出结果的语句，利用自动化的图表统计出来。这个实验由于java和Junit都不熟，有个问题在这里记录下，希望之后可以解决。

　　在待测试代码中存在try catch语句时，如何测试代码进入到catch中。这里并不能直接利用Junit4中的expected来检测待测试进入异常。上述实验中是通过观看输出来判定是否到达这个分支，并不能实现自动测试。