CDI-JSF: Testing CDI code using CDI-Unit

There are a few approaches to test CDI code such as using @Alternative and/or mocking. Another approach, presented here is to use the JGlue project - more exactly the CDI-Unit which is a JUnit4 test runner that enables unit testing Java CDI applications.

For example, let's consider the application from post Inject a Java logger via a CDI producer method - in this application you saw exactly what the name of the post say, how to inject a Java logger via a producer method. Now, let's suppose that we want to write a JUnit test for  the method FooBean#logBuzzAction():

@Named

@RequestScoped

public class FooBean {

 @Inject

 Logger fooLog;

 public void logFooAction() {

  fooLog.info("Log message from FooBean !");

 }

}

In a pretty dummy approach we can try this:

public class LoggerTest {

 @Inject

 FooBean fooBean;

 @Test

 public void testStart() {

  fooBean.logFooAction();

 }

}

Well, obviously this will not work! The problem will be caused by the @Inject part, so is time to find a solution. Add quickly the CDI-Unit dependency in the POM:

<dependency>

 <groupId>org.jglue.cdi-unit</groupId>

 <artifactId>cdi-unit</artifactId>

 <version>3.1.2</version>

 <scope>test</scope>

</dependency>

And specify @RunWith(CdiRunner.class) on your JUnit4 test class to enable injection directly into the test class:

@RunWith(CdiRunner.class)

public class LoggerTest {

 @Inject

 FooBean fooBean;

 @Test

 public void testStart() {

  fooBean.logFooAction();

 }

}

Ok, the FooBean is injected now! But, now we have an unsatisfied dependencies for type Logger.  In order to fix this issue, simply specify MyLogger class as an additional class for this test. This will tell  CDI-Unit to explicitly add a class to the CDI environment:

@RunWith(CdiRunner.class)

@AdditionalClasses(MyLogger.class)

public class LoggerTest {

 @Inject

 FooBean fooBean;

 @Test 

 public void testStart() {

  fooBean.logFooAction();

 }

}

Ok, the last issue that we must solve consist in the fact that there is no active contexts for the request scope, but CDI-Unit has built in support for request, session and conversation scopes using @InRequestScope, @InSessionScope and @InConversationScope. So, let's bring the context in:

@RunWith(CdiRunner.class)

@AdditionalClasses(MyLogger.class)

public class LoggerTest {

 @Inject

 FooBean fooBean;

 @Test

 @InRequestScope

 public void testStart() {

  fooBean.logFooAction();

 }

}

Done! Now the test is ready and you can see it here.