Concepts

Let’s take a closer look at some of the principal concepts that we’ll be covering in this chapter.

WineAppServiceTest: A JUnit test class for the WineAppService EJB

For this chapter’s example, we offer in Listing 13-1 a JUnit test class that contains all of the elements required to unit test EJBs in the Embeddable EJB Container.

Listing 13-1.  WineAppServiceTest.java, a JUnit class for testing EJBs in the WineApp application

public class WineAppServiceTest {
  private static EJBContainer ejbContainer;
  private static NetworkServerControl derbyServer;

  public WineAppServiceTest() {
  }

  @BeforeClass
  public static void setUpClass() throws Exception {
    PrintWriter pw = new PrintWriter(System.out);

    //  Start the Derby Database server, waiting until it is responsive
    //  before continuing
    try {
      derbyServer = new org.apache.derby.drda.NetworkServerControl();
      derbyServer.start(pw);
      int i = 50;
      while (--i > 0) {
        try {
          derbyServer.ping();
          break;
        } catch (Exception ex) {
          System.out.println("Derby Server started; waiting for response...");
        }
        Thread.sleep(100);
      }
    } finally {
      pw.close();
    }

    //  Instantiate an Embeddable EJB Container
    ejbContainer = javax.ejb.embeddable.EJBContainer.createEJBContainer();
  }

  @AfterClass
  public static void tearDownClass() throws Exception {
    //  Close the Embeddable EJB Container, releasing all resources
    ejbContainer.close();

    //  Shutdown the Derby Database server
    derbyServer.shutdown();
  }

  @Before
  public void setUp() {
    //  Inititalize the data in the domain model
    PopulateDemoData.resetData("Chapter13-EmbeddableEJBTests-ResourceLocal", System.out);
  }

  @After
  public void tearDown() {
  }

  /**
   * Test findCustomerByEmail on WineAppService.
   *
   * Assert that the Customer returned is named "James Brown".
   *
   * @throws Exception
   */
  @Test
  public void testFindCustomerByEmail() throws Exception {
    System.out.println("findCustomerByEmail");
    WineAppService wineAppSvcFacade =
        (WineAppService) ejbContainer.getContext().lookup("java:global/classes/WineAppService");
    Customer customer =
        wineAppSvcFacade.findCustomerByEmail(PopulateDemoData.TO_EMAIL_ADDRESS);
    assertEquals("WineAppServiceFacade.findCustomerByEmail(): Checking customer name",
        "James Brown",
        customer.getFirstName() + " " + customer.getLastName());
  }

  /**
   * Test createIndividual() on WineAppService and findCustomerByEmail() on
   * CustomerFacade.
   *
   * Assert that the Individual instance created in createIndividual() has the
   * expected email property.
   * Assert that the Customer retrieved in
   * findCustomerByEmail() has the expected name.
   * Assert that the shippingAddress property is in a managed state after merge
   */
  @Test
  public void testCreateIndividual() throws Exception {
    System.out.println("createIndividual");
    WineAppService wineAppSvcFacade =
        (WineAppService) ejbContainer.getContext().lookup("java:global/classes/WineAppService");
    String email = "[email protected]";
    Individual individual =
        wineAppSvcFacade.createIndividual("Adam", "Beyda", email);
    assertEquals("WineAppServiceFacade.createIndividual(): Checking Individual.email prop",
        email, individual.getEmail());
     
    CustomerFacade custFacade =
        (CustomerFacade) ejbContainer.getContext().lookup("java:global/classes/CustomerFacade");
    Customer customer = custFacade.findCustomerByEmail(email);
    assertEquals("CustomerFacade.findCustomerByEmail(): Checking Customer.email prop",
        "Adam Beyda", customer.getFirstName() + " " + customer.getLastName());

    //  Managed/detached entity state check
    Address shippingAddress = new Address("San Mateo", null, null, null, null);
    customer.setDefaultShippingAddress(shippingAddress);
    customer = custFacade.merge(customer);
    assertNotNull("customer.getDefaultShippingAddress().getId() is null",
        customer.getDefaultShippingAddress().getId());
    assertNotNull("shippingAddress.getId() is null",
        shippingAddress.getId());
  }

  /**
   * Test createIndividual() and createCustomerOrder() on WineAppService,
   * getWineFindByYear() on WineFacade, and merge() on CustomerFacade.
   *
   * Assert that the total value of the created order is 110.
   * Assert that the customerOrder and customer objects are in a managed state
   */
  @Test
  public void testCreateCustomerOrder() throws Exception {
    System.out.println("createCustomerOrder");
    Context context = ejbContainer.getContext();
    WineAppService wineAppSvcFacade =
        (WineAppService) context.lookup("java:global/classes/WineAppService");
    WineFacade wineFacade =
        (WineFacade) context.lookup("java:global/classes/WineFacade");
    CustomerFacade custFacade =
        (CustomerFacade) context.lookup("java:global/classes/CustomerFacade");

    //  Add CartItems to the Customer's cart and merge the customer changes
    final String email = "[email protected]";
    Customer customer = wineAppSvcFacade.createIndividual("Adam", "Beyda", email);
    for (Wine wine : wineFacade.getWineFindByYear(2005)) {
      customer.addCartItem(new CartItem(10, wine));
    }
    customer = custFacade.merge(customer);

    CustomerOrder customerOrder = wineAppSvcFacade.createCustomerOrder(customer);
    Float total = new Float(0);
    for (OrderItem orderItem : customerOrder.getOrderItemList()) {
      total += orderItem.getQuantity() * orderItem.getPrice();
    }
    assertEquals("Checking that customer order totals $270", total, new Float(270));

    //  Query the latest state of our customer from the persistence context
    //  (using a new transaction, courtesy CMT) and check whether it contains a
    //  customer order with a populated 'id' field
    CustomerOrder customerOrder1 =
        wineAppSvcFacade.findCustomerByEmail(email).getCustomerOrderList().get(0);
    assertNotNull("customerOrder1.getId() is null", customerOrder1.getId());

    //  Check whether our original customer order has had its 'id' field auto-populated
    assertNotNull("customerOrder.getId() is null", customerOrder.getId());

    //  Check whether the customer order referenced by our customer
    //  has had its 'id' field auto-populated
    CustomerOrder customerOrder2 = customer.getCustomerOrderList().get(0);
    assertNotNull("customerOrder2.getId() is null", customerOrder2.getId());
  }
}

When this test class is executed in the JUnit tester, each method marked @Test is run in isolation as its own unit test. However, before any of these methods is executed, JUnit performs some initialization steps to instantiate the Embeddable EJB Container and initialize the data in the persistence unit. We will explore the elements of this JUnit class next, beginning with the initialization steps.

Instantiating the Embeddable EJB Container and Starting Derby

Before any test in this class is executed, we want to initialize the Embeddable EJB Container. Because this is a somewhat resource-intensive operation (albeit not as expensive as launching a full-blown GlassFish server), we would like to do this only once each time the JUnit tester is launched. JUnit lets you annotate static methods with @BeforeClass, and it executes these methods once per JUnit session, before the first unit test method is executed on that class. Our class-level setup method is as follows:

@BeforeClass
public static void setUpClass() throws Exception {
  PrintWriter pw = new PrintWriter(System.out);
     
  //  Start the Derby Database server, waiting until it is responsive
  //  before continuing
  try {
    derbyServer = new org.apache.derby.drda.NetworkServerControl();
    derbyServer.start(pw);
    int i = 50;
    while (--i > 0) {
      try {
        derbyServer.ping();
        break;
      } catch (Exception ex) {
        System.out.println("Derby Server started; waiting for response...");
      }
      Thread.sleep(100);
    }
  } finally {
    pw.close();
  }
   
  //  Instantiate an Embeddable EJB Container
  ejbContainer = javax.ejb.embeddable.EJBContainer.createEJBContainer();
}

We begin by starting up the Derby database to allow our persistence unit to connect to a running server. Because the org.apache.derby.drda.NetworkServerControl.start() method is asynchronous, we have to assume that the server might not be available for connections right away, so we ping it in a loop, sleeping briefly between iterations, until it is ready or we decide to time out.

Once Derby is available for connections, we create the Embeddable EJB Container through the javax.ejb.embeddable.EJBContainer.createEJBContainer() call. Our WineAppServiceTest class is called from the JUnit tester, and NetBeans launches the tester with a classpath containing the JPA persistence unit .jar file (from Chapter 7) along with the EJBs defined in our Chapter 13 EJB jar and all of the necessary Java libraries required to run the JUnit framework and instantiate the Embeddable EJB Container. The current (at the time of this writing) GlassFish implementation links to a GlassFish server installation area to provide the services an EJB Container generally requires from its host Java EE server environment. Again, because we are running in a Java SE environment, the Java EE GlassFish server is not actually started, but classes required by the Embeddable EJB Container are loaded as needed from the Java libraries that comprise GlassFish.

At the conclusion of the JUnit session, the Embeddable EJB Container and the Derby Database server must be closed properly to release any resources that they may continue to hold. JUnit invokes methods annotated @AfterClass at this time, and our method tearDownClass() performs these tasks:

@AfterClass
public static void tearDownClass() throws Exception {
  //  Close the Embeddable EJB Container, releasing all resources
  ejbContainer.close();

  //  Shutdown the Derby Database server
  derbyServer.shutdown();
}

Initializing Data in the Persistence Unit

Whereas steps such as starting the Derby and Embeddable EJB Container need to be performed only once per JUnit test session, other initialization steps must be executed prior to every JUnit test. Per-test initialization steps goes in a method (or methods) annotated @Before, like this:

@Before
public void setUp() {
  //  Inititalize the data in the domain model
  PopulateDemoData.resetData("Chapter13-EmbeddableEJBTests-ResourceLocal", System.out);
}

For our tests, we want to ensure that each unit test begins with the same data in the database, so we execute a script that initializes the database and resets the data to the desired state. You may be familiar with this static PopulateDemoData.resetData() method from when it was used in other chapters. Note that we pass the name of a persistence unit so that we can reuse it in different application contexts. The JPA persistence unit in the Chapter07-ServiceIntegration-jpa project defines its own persistence.xml file, and within it a <persistence-unit> named Chapter07-WineAppUnit-ResourceLocal. The <persistence-unit> we are using for our JUnit tests is “Chapter13-EmbeddableEJBTests-ResourceLocal” and it is defined in our context project, Chapter13-EmbeddedEJBTests, in the “Configuration Files” section. Since the entity classes in our JPA persistence unit are visible to our Test/EJB module, we are free to define additional persistence units that reference these same entity classes. JPA is happy to let you define multiple persistence units for the same entity classes, using multiple persistence.xml files if desired, allowing each persistence unit to specify a different database connection, schema generation plan, persistence provider, or any other configuration option. We define a new persistence unit in this case so that we can map them to a database connection that is suited to testing purposes. This connection is described next.

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistencehttp://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
  <persistence-unit name="Chapter13-EmbeddableEJBTests-ResourceLocal" transaction-type="RESOURCE_LOCAL">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <non-jta-data-source>jdbc/__default</non-jta-data-source>
    <class>com.apress.ejb.chapter07.entities.Address</class>
    <class>com.apress.ejb.chapter07.entities.BusinessContact</class>
    <class>com.apress.ejb.chapter07.entities.CartItem</class>
    <class>com.apress.ejb.chapter07.entities.Customer</class>
    <class>com.apress.ejb.chapter07.entities.CustomerOrder</class>
    <class>com.apress.ejb.chapter07.entities.Distributor</class>
    <class>com.apress.ejb.chapter07.entities.Individual</class>
    <class>com.apress.ejb.chapter07.entities.InventoryItem</class>
    <class>com.apress.ejb.chapter07.entities.OrderItem</class>
    <class>com.apress.ejb.chapter07.entities.Supplier</class>
    <class>com.apress.ejb.chapter07.entities.Wine</class>
    <class>com.apress.ejb.chapter07.entities.WineItem</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <properties>
      <property name="eclipselink.ddl-generation" value="drop-and-create-tables"/>
    </properties>
  </persistence-unit>
  <persistence-unit name="Chapter13-EmbeddableEJBTests-JTA" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>jdbc/__default</jta-data-source>
    <class>com.apress.ejb.chapter07.entities.Address</class>
    <class>com.apress.ejb.chapter07.entities.BusinessContact</class>
    <class>com.apress.ejb.chapter07.entities.CartItem</class>
    <class>com.apress.ejb.chapter07.entities.Customer</class>
    <class>com.apress.ejb.chapter07.entities.CustomerOrder</class>
    <class>com.apress.ejb.chapter07.entities.Distributor</class>
    <class>com.apress.ejb.chapter07.entities.Individual</class>
    <class>com.apress.ejb.chapter07.entities.InventoryItem</class>
    <class>com.apress.ejb.chapter07.entities.OrderItem</class>
    <class>com.apress.ejb.chapter07.entities.Supplier</class>
    <class>com.apress.ejb.chapter07.entities.Wine</class>
    <class>com.apress.ejb.chapter07.entities.WineItem</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
  </persistence-unit>
</persistence>

<property name="eclipselink.ddl-generation" value="drop-and-create-tables"/>

The Unit Test Methods

Having now covered the test initialization steps, we turn our attention to the unit tests themselves. Each unit test is annotated @Test to differentiate it from ordinary methods that might also be on the class, and we include three test methods.

The first test, findCustomerByEmail(): executes a single method findCustomerByEmail() on the WineAppService EJB, which returns a Customer instance. It then asserts that the firstname + lastName is “James Brown,” the expected result. Our test class controls the state of the data in the persistence unit, and so it knows what to expect.

/**
 * Test findCustomerByEmail on WineAppService.
 *
 * Assert that the Customer returned is named "James Brown".
 *
 * @throws Exception
 */
@Test
public void testFindCustomerByEmail() throws Exception {
  System.out.println("findCustomerByEmail");
  WineAppService wineAppSvcFacade =
      (WineAppService) ejbContainer.getContext().lookup("java:global/classes/WineAppService");
  Customer customer =
      wineAppSvcFacade.findCustomerByEmail(PopulateDemoData.TO_EMAIL_ADDRESS);
  assertEquals("WineAppServiceFacade.findCustomerByEmail(): Checking customer name",
      "James Brown",
      customer.getFirstName() + " " + customer.getLastName());
}

/**
 * Test createIndividual() on WineAppService and findCustomerByEmail() on
 * CustomerFacade.
 *
 * Assert that the Individual instance created in createIndividual() has the
 * expected email property.
 * Assert that the Customer retrieved in
 * findCustomerByEmail() has the expected name.
 */
@Test
public void testCreateIndividual() throws Exception {
  System.out.println("createIndividual");
  WineAppService wineAppSvcFacade =
      (WineAppService) ejbContainer.getContext().lookup("java:global/classes/WineAppService");
  String email = "[email protected]";
  Individual individual =
      wineAppSvcFacade.createIndividual("Adam", "Beyda", email);
  assertEquals("WineAppServiceFacade.createIndividual(): Checking Individual.email prop",
      email, individual.getEmail());
   
  CustomerFacade custFacade =
      (CustomerFacade) ejbContainer.getContext().lookup("java:global/classes/CustomerFacade");
  Customer customer = custFacade.findCustomerByEmail(email);
  assertEquals("CustomerFacade.findCustomerByEmail(): Checking Customer.email prop",
      "Adam Beyda", customer.getFirstName() + " " + customer.getLastName());

  //  Managed/detached entity state check
  Address shippingAddress = new Address("San Mateo", null, null, null, null);
  customer.setDefaultShippingAddress(shippingAddress);
  customer = custFacade.merge(customer);
  assertNotNull("customer.getDefaultShippingAddress().getId() is null",
      customer.getDefaultShippingAddress().getId());
  assertNotNull("shippingAddress.getId() is null",
      shippingAddress.getId());
}

/**
 * Test createIndividual() and createCustomerOrder() on WineAppService,
 * getWineFindByYear() on WineFacade, and merge() on CustomerFacade.
 *
 * Assert that the total value of the created order is 110.
 * Assert that the customerOrder and customer objects are in a managed state
 */
@Test
public void testCreateCustomerOrder() throws Exception {
  System.out.println("createCustomerOrder");
  Context context = ejbContainer.getContext();
  WineAppService wineAppSvcFacade =
      (WineAppService) context.lookup("java:global/classes/WineAppService");
  WineFacade wineFacade =
      (WineFacade) context.lookup("java:global/classes/WineFacade");
  CustomerFacade custFacade =
      (CustomerFacade) context.lookup("java:global/classes/CustomerFacade");

  //  Add CartItems to the Customer's cart and merge the customer changes
  final String email = "[email protected]";
  Customer customer = wineAppSvcFacade.createIndividual("Adam", "Beyda", email);
  for (Wine wine : wineFacade.getWineFindByYear(2005)) {
    customer.addCartItem(new CartItem(10, wine));
  }
  customer = custFacade.merge(customer);

  CustomerOrder customerOrder = wineAppSvcFacade.createCustomerOrder(customer);
  Float total = new Float(0);
  for (OrderItem orderItem : customerOrder.getOrderItemList()) {
    total += orderItem.getQuantity() * orderItem.getPrice();
  }
  assertEquals("Checking that customer order totals $270", total, new Float(270));

  //  Query the latest state of our customer from the persistence context
  //  (using a new transaction, courtesy CMT) and check whether it contains a
  //  customer order with a populated 'id' field
  CustomerOrder customerOrder1 =
      wineAppSvcFacade.findCustomerByEmail(email).getCustomerOrderList().get(0);
  assertNotNull("customerOrder1.getId() is null", customerOrder1.getId());

  //  Check whether our original customer order has had its 'id' field auto-populated
  assertNotNull("customerOrder.getId() is null", customerOrder.getId());

  //  Check whether the customer order referenced by our customer
  //  has had its 'id' field auto-populated
  CustomerOrder customerOrder2 = customer.getCustomerOrderList().get(0);
  assertNotNull("customerOrder2.getId() is null", customerOrder2.getId());
}

Prerequisites

Before performing any of the steps detailed in the next sections, complete the “Getting Started” section of Chapter 1. This section will walk you through the installation and environment setup required for the samples in this chapter.

Opening the Sample Application

This chapter’s root project holds a dependency on the JPA persistence unit defined in Chapter07-ServiceIntegration-jpa. Launch the NetBeans IDE, and open the Chapter13-EmbeddableEJBTests project using the File Open Project menu. Make sure that the 'Open Required Projects' checkbox is checked.

This project is a stand-alone EJB project, a departure from the other Java EE Application projects that we have used for the other chapters. The project consists of a handful of EJBs to be tested, under the Source Packages folder; a persistence.xml file defining the persistence units used by the EJBs, in the Configuration Files folder; and our JUnit test class in the Test Packages folder. The structure is shown in Figure 13-2.

Compiling the Sources

Invoke the context menu on the Chapter13-EmbeddableEJBTests node, and build the application by selecting the Clean and Build menu option, as shown in Figure 13-3:

Running the JUnit Tests

There are several ways to launch JUnit tests from NetBeans, but for these tests, you will right-click on the WineAppServiceTest class and choose “Test File,” as shown in Figure 13-4:

This step instantiates the Embeddable EJB Container, initializes the database, and executes the three unit tests in our class. The results of the test will appear in the Test Results tab.

As you will see, the second and third tests fail due to assertion failures. So let’s diagnose these problems.