Unit Testing with JUnit Dan Fleck Spring 2010

Unit Testing with JUnit Dan Fleck Spring 2010

What is Unit Testing? ZA procedure to validate individual units of Source Code ZExample: A procedure, method or class ZValidating each individual piece reduces errors when integrating the pieces together later

Automated Unit Tests with JUnit ZJunit is a unit testing framework for Java ZAllows you to write unit tests in Java using a simple interface ZAutomated testing enables running and rerunning tests very easily and quickly

An example unit test @Test public void test. Cell. Change. Propagates() { Spreadsheet = new Spreadsheet(); sheet. put("A 1", "5"); sheet. put("A 2", "=A 1"); sheet. put("A 1", "10"); assert. Equals("10", sheet. get("A 2")); }

Junit Assert Z During a test use Asserts to specify if the test passed or failed Z org. junit. Assert – allows you to test if certain ideas hold by asserting results: http: //junit. sourceforge. net/javadoc/ Z Z Z assert. Equals(expected, actual) assert. Equals(message, expected, actual) assert. Equals(expected, actual, delta) assert. Equals(message, expected, actual, delta) assert. False(condition) assert. False(message, condition) Assert(Not)Null(object) Assert(Not)Null(message, object) Assert(Not)Same(expected, actual) Assert(Not)Same(message, expected, actual) assert. True(condition) assert. True(message, condition)

Junit Methods – Java annotations Z @Before. Class // Run before all tests in class Z public static void set. Up. Class() throws Exception {} Z @After. Class // Run after all tests in class Z public static void tear. Down. Class() throws Exception {} Z @Before // Run before each test in class Z public void set. Up() {} Z @After // Run after each test in class Z public void tear. Down() {} Z @Test Z public void test. Main() { Z http: //www. cavdar. net/2008/07/21/junit-4 -in-60 -seconds/

Junit with Netbeans 1. 2. 3. 4. Note: If this option doesn’t exist use New File->Other->Junit->Test for existing class New File Choose file type: Junit Choose Test for Existing Class Junit test with all stubs created for that class 5. Fill in the individual tests 6. Run Tests (Netbeans options)

Junit Documentation/Tutorials Z http: //junit. sourceforge. net/ Z http: //code. google. com/p/t 2 framework/wiki/J Unit. Quick. Tutorial Z http: //junit. sourceforge. net/doc/testinfected/te sting. htm (older)

Lines of code coverage analysis ZDetermining which lines of code your tests have exercised and which they have not ZAllows you to detect if your unit tests (or system tests) are adequately covering all possibilities or not ZThis is just one way to test

Lines of code coverage analysis with Netbeans ZInstall Unit Test Code Coverage Viewer module Z(See next slide for instructions) ZWrite a Unit Test ZRun test and view highlighted code

Installing the Code Coverage Plugin Z Go into Netbeans -> Tools -> Plugins Search for "Code Coverage" and install it. Z If you don't see it in the list of available plugins, go to the "Settings" tab and check "Netbeans Beta”, reload the catalog, and then try again. Z If you don't see Netbeans Beta in the list on Settings, add the following source for plugins: Netbeans Beta http: //updates. netbeans. org/netbeans/updates/6. 8 /uc/final/beta/catalog. xml. gz

How do you combine coverage with traditional system test scripts? Traditional system testing uses scripts - 1. Enter salary - 2. Enter number of dependents - 3. Click “Calculate Taxes” button - … To combine this with coverage, launch the GUI while capturing coverage statistics Run the test case to determine coverage

How to write test cases ZSee sample system test case ZSee sample unit test case

Junit Example ZTry to write unit tests for /javacode/JUnit. Robot. Example

Summary ZUnit tests can help test the details of your program ZAutomated unit tests provide constant visibility and easy retesting ZTest coverage supplies valuable information when running both unit tests and system tests