JUNIT in Eclipse

1
JUNIT in Eclipse

• Pepper
• Credit to Eclipse Documentation
• http//help.eclipse.org/juno/index.jsp?topic2For
  g.eclipse.jdt.doc.user2FgettingStarted2Fqs-junit
  .htm

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Purpose

• Create test case classes to test individual
  classes or small groups
• Easy to hook test classes to the classes being
  tested
• Test building tools inside Junit class
• Easy to rerun one set of tests or all tests in
  the entire system.
• Easy to supress tests in production

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Startup

• Create a project if you do not have one (file -gt
  New -gt Project)
• Create a folder for your test cases (optional)
• Create a test case for a class you intend to
  write (file -gt new -gt Junit Test Case)
• Choose the type (new junit4 test) and name your
  test class
• You can indicate the name of the class being
  tested, but only after it is created

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Test Case Creation Screen
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How to Create a Test Method

• Type _at_Test to override the test method
• Type test method header -gt public void test2()
• Code the test to just invoke the fail method
• public void testFailure() throws Exception    
  fail()

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Running a test method

• Hit the run button.
• Or Run as -gt Junit test on project or class
• Junit Test runs
• See results in JUnitView
• Failure tab
• Tab for all tests as a tree
• changed code after running test

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Test Result Checking

• http//www.vogella.com/tutorials/JUnit/article.htm
  l
• assertEquals() object comparison using equals
  method
• assertTrue() / assertFalse() compare to boolean
  value
• assertNull() / assertNotNull() is the variable
  null
• assertSame() / assertNotSame() reference same
  object address
• assertThat - uses matcher

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Let's Try

• Write a simple class to be tested
• package testProject
• public class aprogram
• int x 1
• public int myfun (int y)
• x x 1
• return x

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Now code a few tests

• package JUnitTest
• import static org.junit.Assert.
• import org.junit.Test
• import testProject.aprogram
• public class TestFailure
• _at_Test
• public void test1()
• aprogram a new aprogram()
• aprogram b new aprogram()
• assertTrue( b.myfun(3) 2 )
• assertTrue( a.myfun(3) 3 )
• _at_Test
• public void test2()
• //fail("Not yet implemented")
• aprogram a new aprogram()
• aprogram b new aprogram()

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Run the Tests

• See how it points to problem test
• See how one failure in a test class stops the
  running of the next one
• Make both succeed
• Make both fail

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Create a Test Suite

• File -gt New -gt Java -gt Junit -gt Junit Test Suite
• Name the suite (AllTests)
• Select test classes to run