JUnit 軟體測試 架構 JUnit Software Testing Framework

1. JUnit 軟體測試架構JUnit Software Testing Framework 葉秉哲 2002/7/4. http://william.cswiz.org/present/20020704

2. JUnit 的定位 2

3. 大綱 • 引子 • JUnit 基礎篇 • JUnit 進階篇 • 軟體測試基礎 • 推薦讀物 3

4. 一、引子 一流的科學家可以做出很有價值的實驗，產生新知識；二流科學家只是忙於各種實驗，蒐集大量數據，但對知識的累積沒什麼用處。 --- David Salsburg

5. JUnit 簡介 • Regression testing framework written by Erich Gamma and Kent Beck • Open Source • Hosted on SourceForge • Language support • Smalltalk, Java, C++, Perl, Python, etc. • IDE Support • JBuilder, VisualAge, etc. 5

6. What is Software Testing? • The execution of code using combinations of input and state selected to reveal bugs. • The process of devising and executing a test suite that attempts to cause failures, increasing our confidence that failures are unlikely. 6

7. Why Testing? • 目的：矛與盾 • Reveal bugs: quality control • Confidence: qualitative & quantitative • 重要性 • Paradigm↑ productivity↑testing & debugging↑ • Software features that can’t be demonstrated by automated tests simply don’t exist. [Beck 1999, p.45] 7

8. Testing:CMM Perspective The Key Process Areas by Maturity Level Source: Capability Maturity Model for Software, v1.1http://www.sei.cmu.edu/publications/documents/93.reports/93.tr.024.html 8

9. Testing: RUP Perspective Source: Philippe Kruchten, The Rational Unified Process: An Introduction, p.62, Addison Wesley, 1998. 9

10. Testing: XP Perspective If you’re not validating everything all the time,you’re not doing XP. Period. Source: Kent Beck, Extreme Programming Explained: Embrace Change, p.70, Addison Wesley, 1999. 10

11. Test What? • Every artifact during the whole development process should be tested. 11

12. 軟體測試工具分類 12

13. JUnit 的定位 13

14. JUnit Framework 14

15. junit TestCase TestRunner FooTest run 1..* exercise 1..* test1 test2 … How to Test with JUnit? Foo 15

16. Questions… • 如何測試？ strategy • 多少測試才夠？ coverage • 流程？ process • 工具影響？medium is message 16

17. 二、JUnit 基礎篇 Extreme Programmers test everything that could possibly break, using automated tests that must run perfectly all the time. --- Extreme Programming Installed

18. Design Goals of JUnit • Easy to use • Requires no more work than absolutely necessary to write a new test • Leverages existing tests to create new ones • Reusable fixtures to run different tests • Retains values of tests over time • Combines tests from various authors and run them together without fear of interference 18

19. Case Study • 自動產生測試框架 • Using Borland JBuilder 6.0 • 最簡單的完整測試實例 19

20. junit TestCase FooTest 1..* exercise test1 test2 … 實例一 Foo 20

21. 實例一：簡單的待測物 public class Money { private int fAmount; private String fCurrency; public Money(int amount, String currency) { fAmount = amount; fCurrency = currency; } public Money add(Money m) { return new Money(amount() + m.amount(), currency()); } public int amount() { return fAmount; } public String currency() { return fCurrency; } } 21

22. 實例一：產生測試框架 [1/7] Borland JBuilder 6.0 22

23. 實例一：產生測試框架 [2/7] Borland JBuilder 6.0 23

24. 實例一：產生測試框架 [3/7] Borland JBuilder 6.0 24

25. 實例一：產生測試框架 [4/7] Borland JBuilder 6.0 25

26. 實例一：產生測試框架 [5/7] Borland JBuilder 6.0 26

27. 實例一：產生測試框架 [6/7] Borland JBuilder 6.0 27

28. 實例一：產生測試框架 [7/7] import junit.framework.*; public class MoneyTest extends TestCase { public MoneyTest (String s) { super(s); } protected void setUp() { } protected void tearDown() { } public void testAdd() { int val1 = 0; String val2 = "STRING0"; Money money = new Money(val1, val2); Money val1 = null /** @todo fill in non-null value */ ; Money moneyRet = money.add(val1); /** @todo: Insert test code here. Use assertEquals(), for example. */ } } 28

29. Lesson Learned • Code a little, test a little 29

30. junit TestCase TestRunner FooTest run 1..* exercise test1 test2 … 實例二 Foo 30

31. 實例二：待測物，修正版 public class Money implements Cloneable { private int fAmount; private String fCurrency; public Money(int amount, String currency) { /*...*/ } public Money add(Money m) { if (m == null) return (Money) clone(); return new Money(amount() + m.amount(), currency()); } public Object clone() { /*...*/ } public boolean equals(Object obj) { /*...*/ } public int amount() { /*...*/ } public String currency() { /*...*/ } } 31

32. 實例二：測試碼 [1/2] import junit.framework.*; public class MoneyTest extends TestCase { public MoneyTest (String s) { super(s); } public void testNullAdd () { String curr = "NTD"; int val1 = 2002; Money money1 = new Money(val1, curr); Money money2 = null; // null value Money money3 = money1.add(money2); Assert.assertEquals(money1, money3); } 32

33. 實例二：測試碼 [2/2] public void testSimpleAdd() { String curr = "NTD"; int val1 = 2002; int val2 = 345; int val3 = val1 + val2; Money money1 = new Money(val1, curr); Money money2 = new Money(val2, curr); Money money3 = money1.add(money2); assertEquals(money3, new Money(val3, curr)); } } 33

34. Success java -cp lib\junit.jar;. junit.swingui.TestRunner MoneyTest 34

35. Failure 1/2 35

36. Failure 2/2 36

37. Error 1/2 37

38. Error 2/2 38

39. Lessons Learned • Generate & exercise test case(s) • Write test…() method(s) • Verify • Choose a Assert.assert…() • Choose a TestRunner • junit.textui.TestRunner • junit.swingui.TestRunner • Failure vs. error 39

40. 三、JUnit 進階篇 The tests that you write in XP are isolated and automatic. --- Extreme Programming Explained

41. Case Study • Fixture/context 管理 • Test suite 與進入點 • Grouping by tasks • Configuration management • Regression testing 41

42. junit TestCase TestRunner FooTest run 1..* exercise 1..* test1 test2 setUp()tearDown() … 實例三 Foo 42

43. 實例三：測試碼 [1/2] import junit.framework.*; public class MoneyTest extends TestCase { private Money money1, money2, money3; public MoneyTest(String s) { /*...*/ } protected void setUp() { String curr = "NTD"; int val1 = 2002; int val2 = 345; money1 = new Money(val1, curr); money2 = new Money(val2, curr); money3 = new Money(val1 + val2, curr); } 43

44. 實例三：測試碼 [2/2] protected void tearDown() { } public void testNullAdd() { Money money10 = money1.add(null); // null value assertEquals(money1, money10); } public void testSimpleAdd() { Money money10 = money1.add(money2); assertEquals(money3, money10); } } 44

45. Lessons Learned • Fixture • OverridessetUp() • OverridestearDown() • Each test…() method is isolated 45

46. junit TestSuite TestCase FooTest run 1..* exercise test1 test2 … test suite 實例四 TestRunner 1..* Foo test case 46

47. 實例四：測試碼 [1/3] import junit.framework.*; public class MoneyTest extends TestCase { private Money money1, money2, money3; public MoneyTest (String s) { /*...*/ } protected void setUp() { /*...*/ } public void testNullAdd() { /*...*/ } public void testSimpleAdd() { /*...*/ } 47

48. 實例四：測試碼 [2/3] // [interactive mode] // entry point of the whole test suite! /* // Version 1 public static Test suite() { TestSuite suite = new TestSuite(); suite.addTest(new MoneyTest("testNullAdd")); suite.addTest(new MoneyTest("testSimpleAdd")); return suite; } */ // Version 2 public static Test suite() { return new TestSuite(MoneyTest.class); } 48

49. 實例四：測試碼 [3/3] // [batch mode] // entry point of the whole test suite! public static void main(String args[]) { junit.textui.TestRunner.run(suite()); } } 49

50. Lessons Learned • Test case suite • Write a suite() as the interactive mode entry point • Write a main() as the batch mode entry point 50