Home > Articles > Programming > Java

  • Print
  • + Share This
Like this article? We recommend

Adding Fixtures

Now, let's consider the case in which each of the tests that you design needs a common set of objects. One approach can be to create those objects in each of the methods. Alternatively, the JUnit framework provides two special methods, setUp() and tearDown(), to initialize and clean up any common objects. This avoids duplicating the test code necessary to do the common setup and cleanup tasks. These are together referred to as fixtures. The framework calls the setup() before and tearDown() after each test method—thereby ensuring that there are no side effects from one test run to the next. This also implies that there is no fixed order in which the framework may execute the test methods during a run of the test runner. So in all cases, avoid temporal coupling of the tests. If however, it is necessary to perform the tests in some specific order, we can use the static suite() method to ensure the ordering. For example, you can expect that the tests below would be executed in the order indicated.

//define a test suite – ensure the order of the tests
public static Test suite() {
     TestSuite testsToRun = new TestSuite();
     testsToRun.addTest(new MyTest("testFirstMethod"));
     testsToRun.addTest(new MyTest("testSecondMethod"));
    return testsToRun
  }

One important thing to remember is that one should not use the TestCase constructor for any of the setup code, as shown in the code below. Any exception to the setup code will simply be reported as an AssertonFailedError by the framework, and the resulting stack trace will not be very helpful for the developer.

// extend the TestCase class
public class MyTest extends TestCase {

//pass the name of the test to the super class
  public MyTest(String name) {
    super(name);
// place the setup code here – Bad Idea!
  }

Let's consider an application for a catalog of products. Each product has a name, a quantity, and a sales price. A catalog may have 0..n number of products (see Figure 3). The code for the two objects is included in the Resources section at the end of the article.

Figure 3Figure 3 Object relationships for the catalog.

Very briefly, the classes have the following member variables, and access to them is provided using different get and set methods:

// Class Catalog
public class Catalog {
    private String title;
    private Vector products = new Vector();
}

//Class Product
public class Product {
    private String name;
    private int quantity;
    private float price;

}

Now let's consider a TestCase written to test the details of these classes:

package junittest;

//import the junit.framework package
import junit.framework.*;

// extend the TestCase class
public class CatalogTest extends TestCase {

  private Catalog myCatalog;
  private Product aProduct;

  /**
   * Constructs a CatalogTest with the specified name.
   * @param name Test case name.
   */
  public CatalogTest(String name) {
    super(name);
  }

  /**
   * Sets up the test fixture – initializes common objects.for tests
   * This is called before every test case method.
   */
  protected void setUp() {

    myCatalog = new Catalog();
    aProduct = new Product("Product 1", 4, 20.05);
    myCatalog.addProduct(aProduct);
  }

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

  /**
   * Tests adding a product to the catalog.
   */
  public void testProductAdd() {

    int beforeAdd = myCatalog.getItemCount();
    Product newProduct = new Product("Product 2", 2, 10.56);
    myCatalog.addProduct(newProduct);
    assertEquals(beforeAdd+1, myCatalog.getItemCount());
  }

  /**
   * Tests removing a product by name in the catalog.
   * This test is successful if the 
   * ProductNotFoundException is not raised.
   */
  public void testProductRemoveByName() {

  try {

    int beforeRemove = myCatalog.getItemCount();
    String productNameToRemove = "Product 1";
    myCatalog.removeProductByName(productNameToRemove);
    assertEquals(beforeRemove-1, myCatalog.getItemCount());

    } catch(ProductNotFoundException failure) {
      fail("Should never raise a ProductNotFoundException");
    }

  }


  /**
   * Tests removing a product in the catalog.
   * This test is successful if the 
   * ProductNotFoundException is not raised.
   */
  public void testProductRemove() {

  try {

    int beforeRemove = myCatalog.getItemCount();
    Product producttoRemove = new Product(aProduct);
    myCatalog.removeProduct(producttoRemove);
    assertEquals(beforeRemove-1, myCatalog.getItemCount());

    } catch(ProductNotFoundException failure) {
      fail("Should never raise a ProductNotFoundException");
    }

  }

  /**
   * Tests the emptying of the catalog.
   */
  public void testClear() {

    myCatalog.clear();
    assertTrue(myCatalog.isEmpty());
  }

  /**
   * Tests removing a product that does not exist in the catalog 
   * This test is successful if the 
   * ProductNotFoundException is raised.
   */
  public void testProductNotFound() {

    try {

      Product naProduct = new Product("Product NA", 2, 5.65);
      myCatalog.removeProduct(naProduct);
      fail("Should raise a ProductNotFoundException");

    } catch(ProductNotFoundException success) {
      // successful test
    }
  }

  /**
   * Hook to define test cases to junit
   *
   * @param args Optional list of tests to execute.
   * @return List of tests to execute.
   */


  public static Test suite(String[] args) {

     if (args.length == 0){
     // run all tests defined in class.
       return new TestSuite(CatalogTest.class);
     }
     else{
       TestSuite testsToRun = new TestSuite();
       for (int i = 0; i < args.length; i++){
        testsToRun.addTest(new CatalogTest(args[i]));
       }

       return testsToRun;
     }
  }

  /**
  * Main program for external invocation in command line mode
  * @param List of tests to execute via suite()
  */

public static void main(String args[]) throws ClassNotFoundException{

   junit.textui.TestRunner.run(suite(args));
   return;
 }

}

The test methods should be self-explanatory. We will discuss three of the methods: the two private fixture methods setUp() and tearDown() and the public method suite(). The setUp() method is used to initialize the Catalog object and assign it one Product. The tearDown() method is used to release the Catalog object. The static suite() factory method creates a TestSuite containing the tests that the runner needs to execute. By default, it picks up all the testMethodName() calls of the TestCase. Alternatively, one can specify the individual method to be called on the command line and it builds a collection that it passes to the runner. After you have compiled the classes, go ahead and type the following on the command line:

java junit.swingui.TestRunner junittest.CatalogTest

This code runs the test in the JUnit swing test runner, as shown in Figure 4. As shown in the figure, all the tests that we defined the CatalogTest class were run successfully.

Figure 4Figure 4 JUnit swing test runner.

Now type the following command:

java junittest.CatalogTest testProductAdd testProductRemove

The output looks like Figure 5. Only the two tests defined on the command line were run. This was achieved using the suite() method, as described earlier.

Figure xxxFigure 5 Console output for the two tests.

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020