Laurie Williams, Dright Ho, Sarah Smith
Department of Computer Science
North Carolina State University

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Eclipse v. 3.0 and Rational XDE v.2003 come with JUnit built into the Workbench. Eclipse allows you to quickly create test case classes and test suite classes to write your test code in. With Eclipse, Test Driven Development (TDD), becomes very easy to organize and implement.

The class that you will want to test is created first so that Eclipse will be able to find that class when you build the test case class. The test cases are built with the needed imports and extensions to get JUnit to run. Once the test case class is built the actual test cases are then coded in by the programmer.

The creation of test suites in Eclipse is even easier. When you create a test suite, Eclipse will name it for you and will specify all of the test cases in the scope of the project that it can find. The code to run the test suite and to add all of the specified test cases you've created, is added to the test suite for you.

Reminder of JUnit Naming Conventions:

• Test Case Class: Named [classname]Test.java, where classname is the name of the class that is being tested.
• Test Case Method: Named test[methodname], where methodname is the name of the method that is tested.
• Test Suite: Default name for Eclipse is AllTests.java

It is considered a best practice in testing, to separate the test case code from the application code. It is also a good idea to separate your JUnit and FIT tests as well. Here is an example file structure that helps with this:

File Structure Before Adding fit.jar and junit.jar to the Build Path	File Structure After Adding fit.jar and junit.jar to the Build Path

Most projects that you create will have a src/ folder that contain the main application code, a bin/ folder that contain the compiled .class files, and a lib/ folder that contains jar files that need to be on the project's class path. In order to use FitRunner, fit.jar needs to be on the class path. Since FIT requires the JUnit libraries, junit.jar must also be on the build path.

The acctest/spec/ folder will contain the specification HTML tables of your FIT acceptance tests, while acctest/result/ will contain the HTML tables that show the results of your FIT acceptance tests. It is best to keep a clean file of your test specification so that you can rerun the tests on a clean file. The acctest/fixtures/ folder will contain the Java fixtures that run your FIT acceptance tests. The unittests/ folder will contain your JUnit test cases. The models/ folder may contain your models that are generated in Rational XDE.

1.1 Putting junit.jar on the Build Path

1.1.1 Right click on the project and select Properties. In the left column select Java Build Path. To the right select the Libraries tab. Click the Add External JARs... button. You should start off in the Eclipse install directory, otherwise search through the file system until you find the Eclipse install directory.

Note: The Eclipse install directory is usually under the C:/ on most computers in the VenIII lab. This is where it is suggested that you install Eclipse on the Eclipse web site.

1.1.2 Under the Eclipse install directory select plugins/org.junit_3.8.1/junit.jar. Click OK.

OR

1.2.1 Download junit.jar from here, or from www.junit.org. Add junit.jar to your lib/ directory in your project.

1.2.2 Right click on the project and select Properties. In the left column select Java Build Path. To the right select the Libraries tab. Click the Add JARs... button. Select your project, and go down through the tree until you find junit.jar under the lib folder. Select junit.jar and Click OK.

Note: After you add junit.jar to the build path, it will no longer be displayed in the lib/ directory in the Package Explorer view of Eclipse. The jar file is still located in the lib/ directory when you explore it from outside of Eclipse, but since it is now on the build path inside of Eclipse, it has its own listing in the project.

JUnit convention is that there is a test class created for every application class. Usually all paths through each method in a class are tested in a unit test; however, you do not need to test getter and setter methods since they are trivial.

2.1 There are five ways to create a JUnit Test Case Class. First, select the directory (usually unittests/) that you wish to create the test case class in.

2.1.1 Select File > New > JUnit Test Case

2.1.2 Select the arrow of the button in the upper left of the toolbar. Select JUnit Test Case ,

2.1.3 Right click on a package in the Package Explorer view in the Java Perspective, and select JUnitTestCase, or

2.1.4 Click on the arrow of the icon in the toolbar. Select JUnit Test Case .

2.1.5 You can create a normal Java class as shown in the Eclipse tutorial, but include junit.framework.TestCase as the super class of the test class you are creating.

2.2 Check to make sure that you are creating the TestCase in the proper package. Give the test case a name.

2.2.1 Use the Browse button to search for a different super class. The default super class is junit.framework.TestCase.

2.2.2 Check which method stubs you would like to create. You can create a main method, setUp(), tearDown(), or a constructor(), but all of these are optional. A constructor is only run when the test case is first instantiated, but the setUp() and tearDown() methods are run before and after, respectively, each test case is run.

2.2.3. You can browse the application that you are creating for a class that you wish to test, or this could be left blank if you will generate the class while creating while creating the test.

2.3 Click Finish. The new test case class will be open in the editor.

2.4 Below is a test case template from the JUnit FAQ. This test class demonstrates the basic functionality of the setUp() and tearDown() methods, and gives example test cases. The testForException() method demonstrates how to test that an exception is properly thrown.

Note: All source methods must be public or protected, not private, in order to be tested by JUnit.

import junit.framework.TestCase;


public class SampleTest extends TestCase {


     private java.util.List emptyList;


     /**
      * Sets up the test fixture. 
      * (Called before every test case method.) 
      */ 
     protected void setUp() { 
          emptyList = new java.util.ArrayList();
     } 


     /**
      * Tears down the test fixture. 
      * (Called after every test case method.) 
      */ 
     protected void tearDown() { 
          emptyList = null; 
     } 


     public void testSomeBehavior() { 
          assertEquals("Empty list should have 0 elements", 0, emptyList.size());
     } 

     public void testForException() { 
          try { 
               Object o = emptyList.get(0); 
               fail("Should raise an IndexOutOfBoundsException");
          } 
          catch (IndexOutOfBoundsException success) {
          } 
     } 

}

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