Difference between revisions of "User:Michael.norman.oracle.com/Info on JUnit4"

Revision as of 15:41, 4 December 2007

Information on JUnit4

• successor to most widely used unit-testing framework for Java, JUnit3
• under active development (last JUnit3 release 3.8.2 2006-03-03)
  • JUnit 4 released 2006-02-16
    • 4.1 2006-04-27
    • 4.2 2006-11-16
    • 4.3 2006-11-16
      • 4.3.1 2007-03-28
    • 4.4 (current as of 071204) 2007-07-18

based on Java 5 features

• no longer need to extend class TestCase
• test-method names do not have to start with the prefix test
• mark your test method with a @Test annotation
• use static import's to get assert methods (instead of via inheritance)

import junit.framework.TestCase;
import org.junit.Test;
import static org.junit.Assert.*;

public class CalculatorTest extends TestCase {

    @Test
    public void testadd() { 
        ....
        assertEquals(4, calculator.add( 1, 3 ));
    } 
}

improved test lifecycle management

• setUp() and tearDown() replaced with @Before and @After annotations (allows for multiple @Before/@After methods)

public class CalculatorTest {

  @Before
  public void prepareTestData() { ... }

  @Before
  public void setupMocks() { ... }

  @After
  public void cleanupTestData() { ... }
}

improved fixture management

JUnit3:

import junit.framework.*;
import junit.extensions.TestSetup;

public class AllTestsOneTimeSetup {

   public static Connection conn; // database connection

   public static Test suite() {
       TestSuite suite = new TestSuite();
       TestSetup wrapper = new TestSetup(suite) {
           protected void setUp() {
               setUpDatabaseConnection();
           }
           protected void tearDown() {
               tearDownDatabaseConnection();
           }
       };
       return wrapper;
   }

   public static void setUpDatabaseConnection() {
       // one-time initialization code
       conn = ...;
   }

JUnit4: multiple @BeforeClass/@AfterClass annotations

import org.junit.AfterClass;
import org.junit.BeforeClass;

public class TestWithDatabaseConnection {

   public static Connection conn; // database connection fixture
   public static Object foo; // another fixture

   @BeforeClass
   public static void setUpDatabaseConnection() {
       conn = ...;
   }

   @BeforeClass
   public static void setUpFoo() {
       foo= ...;
   }

   @AfterClass
   public static void tearDownDatabaseConnection() {
       conn.close() ...;
   }

}