1. 1 CSC/ECE 517 Fall 2010 Lec. 2 Overview of Eclipse Lectures 1.Overview 2.Installing and Running 3.Building and Running Java Classes 4.Debugging 5.Testing with JUnit 6.Refactoring 7.Version Control Lecture 2 “Lecture 0” Lecture 3

2. 2 CSC/ECE 517 Fall 2010 Lec. 2 Module Road Map 1.Overview 2.Installing and Running 3.Building and Running Java Classes 4.Debugging  Debug Perspective  Debug Session  Breakpoint  Debug Views  Breakpoint Types  Evaluating and Displaying Expressions 5.Testing with JUnit 6.Refactoring 7.Version Control with CVS

3. 3 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Debugging in Eclipse The Java Debugger  Part of Eclipse Java Development Tools (JDT)  More than System.out.printn( ̎̎̎̎ error ̎̎̎̎ )  Detects errors as code executes  Correct errors as code executes  Actions you can perform debugging include:  Control Execution  Set simple breakpoints  Set conditional breakpoints  Review and change variable values  Hot code replace (feature new to JRE 1.4)

4. 4 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Debug Perspective Threads and Monitor View Console View Outline View Editor View Tasks View Variable View

5. 5 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Simple Breakpoint Breakpoint  Stops the execution of a program at the point  Thread suspends at the location where the breakpoint is set Setting a breakpoint  CTRL+Shift+B at current point in editor line  Double click in editor’s marker bar at current line

6. 6 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Starting a Debugging Session Select Java class containing the following:  main() method  Resulting execution will pass breakpoint Select Run » Debug As » Java Application Or Select Debug As » Java Application from the drop-down menu on the Debug tool bar.

7. 7 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Debug Session Execution suspends prior to the line with a breakpoint You can set multiple breakpoints

8. 8 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Deleting Breakpoints Double-click on the breakpoint in the editor

9. 9 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Control Execution From Breakpoint… Step Into or F5:  For methods, execute method and suspend on first statement in the method  For assignments, similar to Step Over  For conditionals, similar to Step Over Step Over or F6  Execute next statement Step Return or F7  Resume execution to the end of the method on the next line after it was invoked

10. 10 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Control Execution From Breakpoint Resume or F8  Continue execution until program ends or another breakpoint is reached Terminate  S tops the current execution thread

11. 11 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Variables and Fields To see the values bound to fields:  Use Variables View  Select variable in editor and select Inspect

12. 12 CSC/ECE 517 Fall 2010 Lec. 2 public class Debug { private int something = 0; private Vector list = new Vector(); public void firstMethod(){ thirdMethod(something); something = something + 1; } public void secondMethod(){ thirdMethod(something); something = something + 2; } public void thirdMethod(int value){ something = something + value; } public static void main(String[] args) { Debug debug = new Debug(); debug.firstMethod(); debug.secondMethod();} } Debugging » Code Debugging in this Module

13. 13 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Variables View Shows all fields of instance where breakpoint occurred  Select this to see all fields  Select any field to see value  If field is bound to an object, you can select Inspect from the menu to view its fields and values

14. 14 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Changing Field Values To change field value:  Select field in Variables view  Select Change Variable Value from the menu  Enter new value into Set Variable Value window  Click OK

15. 15 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Expressions View Remembers all objects you have inspected Displays the fields of the object  You can see the values of the fields  You can Inspect the fields Opens when:  You Inspect an object  You click on the Expressions tab

16. 16 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Breakpoint View Lists all available breakpoints Can be used for manipulating breakpoints (through the views menu):  Enabling  Disabling  Removing Also displays breakpoints properties Accessed like other debugging views

17. 17 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Debug View Shows:  Active threads  Current stack frame when execution has stopped  Previous stack frames Method and variables are shown in the editor for the selected frame  Update in the editor updates the source

18. 18 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Breakpoint Types Breakpoints can be set for the following Java entities:  Line (simple breakpoint)  Method  Field (watchpoint)  Java Exception Each breakpoint is set a different way and has different properties

19. 19 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Method Breakpoints To set method breakpoint:  Select method in the Outline View  From context menu select Toggle Method Breakpoint To set breakpoint’s properties:  Select breakpoint in editor. From the context menu, select Breakpoint Properties.  In the Properties dialog, Check Enabled to enable the breakpoint  Check Hit Count to enable hit count. Breakpoint suspends execution of a thread the nth time it is hit, but never again, until it is re-enabled or the hit count is changed or disabled.  Choose Enable condition to have breakpoint enabled only if the specified condition occurs. condition is 'true' option: Breakpoint stops if the condition evaluates to true. The expres- sion provided must be a boolean expression. value of condition changes option: Breakpoint stops if result of the condition changes.

20. 20 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Field Breakpoints Also known as watchpoint To set the watchpoint:  Select field in the Outline View  From context menu select Toggle Watchpoint To set watchpoint’s properties:  Select breakpoint in editor  Select Breakpoint Properties.. from context menu  Set properties as desired  Access/modification, enable Execution suspended on access/modification of field

21. 21 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Java Exception Breakpoint To Add Java Exception Point:  Select Run » Add Java Exception Breakpoint from main menu  Enter exception type  Specify what triggers a breakpoint:  Caught exception  Uncaught exception  Both

22. 22 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » How To Debug Here are simple steps for debugging in Eclipse:  Set your breakpoints  Hit a breakpoint during execution  Walk/step through code to other breakpoints  Follow along in editor  Inspect/Display interesting fields  Watch the Console for things to happen

23. 23 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Summary You have learned:  The views in the Debug Perspective  Typical debug session  How to use the Inspector  About the different types of breakpoints  How to set breakpoints  How step around your code doing debugging

24. 24 CSC/ECE 517 Fall 2010 Lec. 2 Debugging » Exercise 1 Set a breakpoint in the firstMethod method of the class Debug class (you can paste it from the lecture notes). Start a debug session. What happens to the program execution? What do you see in the debug windows?

25. 25 CSC/ECE 517 Fall 2010 Lec. 2 Module Road Map 1.Overview 2.Installing and Running 3.Building and Running Java Classes 4.Debugging 5.Testing with JUnit  What is JUnit?  Where Does it Come From?  Working with Test Cases  Working with Test Suites  JUnit Window 6.Refactoring 7.Version Control with CVS

26. 26 CSC/ECE 517 Fall 2010 Lec. 2 What is JUnit? Regression testing framework Written by Erich Gamma and Kent Beck Used for unit testing in Java Open Source Released under IBM's CPL

27. 27 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Where Does JUnit Come From? JUnit’s web site: http://junit.org/index.htm Eclipse includes JUnit  Eclipse provides new GUI to run JUnit test cases and suites  JDT tools include a plug-in that integrates JUnit into the Java IDE  Allows you to define regression tests for your code and run them from the Java IDE. You can run your unit tests outside of Eclipse  If you wish using TestRunner  Using JUnit’s Window

28. 28 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Including JUnit in a Project In the Package window, right- click on the name of the project Choose “Properties”; then select “Java Build Path” Click on the “Libraries” tab, and then choose the “Add Library” button on the right. Select “Junit” and click “Finish”.

29. 29 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Eclipse JUnit Setup Eclipse preferences can be set in the JUnit Preferences window (Window » Preferences from the main menu. Expand Java in the Preferences window) For the most part you can leave the preferences alone Filters needed to identify packages, classes, or patterns that should not be shown in the stack trace of a test failure

30. 30 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit Test Cases JUnit Test Cases  Test case  Runs multiple tests  Implemented as subclass of TestCase  Define instance variables that store the state of the tests in the class  Initialize TestCase by overriding setUp method  Clean-up after test case is done by overriding tearDown method  The Test framework will invoke the setUp and tearDown methods.

31. 31 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Creating JUnit Test Cases in Eclipse Create a new package to contain your test case classes Add the JUnit JAR file to the project’s buildpath

32. 32 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Creating JUnit Test Cases in Eclipse Select your testing package From the context menu select New » JUnit Test Case. This opens the New JUnit Test Case Wizard. Fill in the name of your test case in the Name field. Select the method stubs that you want Eclipse to generate This will create the corresponding class in your testing package

33. 33 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit TestCase Template public class NewTestCase extends TestCase { public static void main(String[] args) { } public NewTestCase(String arg0) { super(arg0); } protected void setUp() throws Exception { super.setUp(); } protected void tearDown() throws Exception { super.tearDown(); }

34. 34 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Adding Tests to Test Cases Any method in a TestCase class is considered a test if it begins with the word “test”.  You can write many tests (have many test methods) Each test method should use a variety of assert… methods to perform tests on the state of its class.  Assert methods are inherited

35. 35 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit Assert Methods Assert methods include:  assertEqual(x,y)  assertFalse(boolean)  assertTrue(boolean)  assertNull(object)  assertNotNull(object)  assetSame(firstObject, secondObject)  assertNotSame(firstObject, secondObject)

36. 36 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Adding Two Tests to JUnit Test Case public class NewTestCase extends TestCase { public static void main(String[] args) { } public NewTestCase(String arg0) { super(arg0); } protected void setUp() throws Exception { super.setUp(); } protected void tearDown() throws Exception { super.tearDown(); } public void testCompareSucceed() { assertEquals(0, 0); //this assertion will succeed } public void testCompareFail() { assertEquals(0, 1); //this assertion will fail }

37. 37 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Running JUnit Test Case Select TestCase class From the Run menu select Run » Run As » JUnit Test This will run the tests in your TestCase class along with the setUp and tearDown methods You will then get a report in the JUnit window

38. 38 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit Window Red indicates a test has failed You can see which test failed You can see the call trace leading to the failure If you wish to see the tests in TestCase click on the Hierarchy tab

39. 39 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit Window You can see how many tests ran How many failures occurred You can see the details of the failure Errors occur when exceptions are thrown

40. 40 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Creating JUnit Test Suite Test Suite  Runs multiple test cases or suites To create a TestSuite  Select your testing package  From the context menu select New » Other… Then from the Wizard select Java » JUnit » JUnit Test Suite

41. 41 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Creating JUnit Test Suite Fill in the name of your TestSuite class Select the TestCases to include in your TestSuite

42. 42 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Unit Test Suite Template import com.test; import junit.framework.Test; public class AllInclusiveTestSuite { public static Test suite() { TestSuite suite = new TestSuite("Test for com.test"); //$JUnit-BEGIN$ suite.addTestSuite(NewTestCase.class)); suite.addTestSuite(SecondTestCase.class)); //$JUnit-END$ return suite; }

43. 43 CSC/ECE 517 Fall 2010 Lec. 2 Testing » Running JUnit Test Suite Select TestSuite class From the Run menu select Run » Run As » JUnit Test This will run the test cases in your TestSuite class You will then get a report in the JUnit Window

44. 44 CSC/ECE 517 Fall 2010 Lec. 2 Testing » JUnit Test Interface The JUnit classes TestCase and TestSuite both implement the JUnit Test interface Therefore, you can add JUnit TestSuites to other TestSuites public static Test suite() { TestSuite suite = new TestSuite("Test for testing"); //$JUnit-BEGIN$ suite.addTestSuite(FirstTestCase.class); suite.addTestSuite(SecondTestCase.class); suite.addTest(AllTests.suite()); //$JUnit-END$ return suite; }

45. 45 CSC/ECE 517 Fall 2010 Lec. 2 Exercise 2 Create a JUnit test case class TestClass for the package example1 of the project Lecture 2. Add a test method testBoolean to the class TestClass. In the method testBoolean, invoke the assert routine assertTrue with the argument “0” (FALSE). Run the test case. What do you see in the JUnit window? Now invoke the assertTrue routine with the argument “1” (TRUE). Run the test case. What is the output in the JUnit window?