The org.springframework.mock.jndi package contains an implementation of the JNDI SPI, which is useful for setting up a simple JNDI environment for test suites or stand-alone applications. If, for example, JDBC DataSources get bound to the same JNDI names in test code as within a J2EE container, both application code and configuration can be reused in testing scenarios without modification.

The org.springframework.mock.web package contains a comprehensive set of Servlet API mock objects, targeted at usage with Spring's Web MVC framework, which are useful for testing web contexts and controllers. These mock objects are generally more convenient to use than dynamic mock objects (e.g., EasyMock) or existing Servlet API mock objects (e.g., MockObjects).

The org.springframework.mock.web.portlet package contains a set of Portlet API mock objects, targeted at usage with Spring's Portlet MVC framework.

The org.springframework.test.util package contains ReflectionTestUtils, which is a collection of reflection-based utility methods for use in unit and integration testing scenarios in which the developer would benefit from being able to set a non-public field or invoke a non-public setter method when testing application code involving, for example:

The org.springframework.test.web package contains AbstractModelAndViewTests, which serves as a convenient base class for JUnit 3.8 based unit tests dealing with Spring MVC ModelAndView objects. When developing against Java 1.4 and higher (e.g., in combination with JUnit 4+, TestNG, etc.), you have the option of using the ModelAndViewAssert class (in the same package) to test your ModelAndView related functionality.

Tip: depending on your testing environment, either extend AbstractModelAndViewTests or use ModelAndViewAssert directly and then use MockHttpServletRequest, MockHttpSession, etc. from the org.springframework.mock.web package to test your Spring MVC Controllers.

Spring integration testing support frameworks provide consistent loading of Spring ApplicationContexts and caching of those contexts. Support for the caching of loaded contexts is important, because if you are working on a large project, startup time may become an issue - not because of the overhead of Spring itself, but because the objects instantiated by the Spring container will themselves take time to instantiate. For example, a project with 50-100 Hibernate mapping files might take 10-20 seconds to load the mapping files, and incurring that cost before running every single test in every single test fixture will lead to slower overall test runs that could reduce productivity.

Test classes will generally provide an array containing the resource locations of XML configuration metadata - typically on the classpath - used to configure the application. This will be the same, or nearly the same, as the list of configuration locations specified in web.xml or other deployment configuration.

By default, once loaded, the configured ApplicationContext will be reused for each test. Thus the setup cost will be incurred only once (per test fixture), and subsequent test execution will be much faster. In the unlikely case that a test may 'dirty' the application context, requiring reloading - for example, by changing a bean definition or the state of an application object - Spring's testing support provides mechanisms to cause the test fixture to reload the configurations and rebuild the application context before executing the next test.

Context management and caching with:

When Spring integration testing support frameworks load your application context, they can optionally configure instances of your test classes via Dependency Injection. This provides a convenient mechanism for setting up test fixtures using pre-configured beans from your application context. A strong benefit here is that you can reuse application contexts across various testing scenarios (e.g., for configuring Spring-managed object graphs, transactional proxies, DataSources, etc.), thus avoiding the need to duplicate complex test fixture set up for individual test cases.

As an example, consider the scenario where we have a class, HibernateTitleDao, that performs data access logic for say, the Title domain object. We want to write integration tests that test all of the following areas:

Dependency Injection of test fixtures with:

One common issue in tests that access a real database is their affect on the state of the persistence store. Even when you're using a development database, changes to the state may affect future tests. Also, many operations - such as inserting to or modifying persistent data - cannot be performed (or verified) outside a transaction.

The Spring integration testing support frameworks meet this need. By default, they create and roll back a transaction for each test. You simply write code that can assume the existence of a transaction. If you call transactionally proxied objects in your tests, they will behave correctly, according to their transactional semantics. In addition, if test methods delete the contents of selected tables while running within a transaction, the transaction will roll back by default, and the database will return to its state prior to execution of the test. Transactional support is provided to your test class via a PlatformTransactionManager bean defined in the test's application context.

If you want a transaction to commit - unusual, but occasionally useful when you want a particular test to populate or modify the database - the Spring integration testing support frameworks can be instructed to cause the transaction to commit instead of roll back either by calling an inherited hook-method or by declaring a specific annotation.

Transaction management with:

The Spring integration testing support frameworks provide several abstract support classes that can simplify writing integration tests. These base test classes provide well defined hooks into the testing framework as well as convenient instance variables and methods, allowing access to such things as:

Often you will provide an application-wide superclass for integration tests that provides further useful instance variables used in many tests.

Support classes for:

AbstractSingleSpringContextTests provides context management and caching support for JUnit 3.8 based test cases and exposes a protected method that subclasses can override to provide the location of context definition files:

protected String[] getConfigLocations()

Implementations of this method must provide an array containing the resource locations of XML configuration metadata - typically on the classpath - used to configure the application. This will be the same, or nearly the same, as the list of configuration locations specified in web.xml or other deployment configuration. As an alternative you may choose to override one of the following. See the respective JavaDoc for further details.

protected String[] getConfigPaths()

protected String getConfigPath()

By default, once loaded, the configuration file set will be reused for each test case. Thus the setup cost will be incurred only once (per test fixture), and subsequent test execution will be much faster. In the unlikely case that a test may 'dirty' the application context, requiring reloading - for example, by changing a bean definition or the state of an application object - you can call the setDirty() method on AbstractSingleSpringContextTests to cause the test fixture to reload the configurations and rebuild the application context before executing the next test case. As an alternative, if you are developing against Java 5 or greater and extending AbstractAnnotationAwareTransactionalTests, you may annotate your test method with @DirtiesContext to achieve the same effect.

When AbstractDependencyInjectionSpringContextTests (and subclasses) load your application context, they can optionally configure instances of your test classes by Setter Injection. All you need to do is to define instance variables and the corresponding setter methods. AbstractDependencyInjectionSpringContextTests will automatically locate the corresponding object in the set of configuration files specified in the getConfigLocations() method.

Consider the scenario where we have a class, HibernateTitleDao (as outlined in the Common goals section). Let's look at a JUnit 3.8 based implementation of the test class itself (we will look at the configuration immediately afterwards).

public final class HibernateTitleDaoTests extends AbstractDependencyInjectionSpringContextTests  {

    // this instance will be (automatically) dependency injected    
    private HibernateTitleDao titleDao;

    // a setter method to enable DI of the 'titleDao' instance variable
    public void setTitleDao(HibernateTitleDao titleDao) {
        this.titleDao = titleDao;
    }

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }

    // specifies the Spring configuration to load for this test fixture
    protected String[] getConfigLocations() {
        return new String[] { "classpath:com/foo/daos.xml" };
    }

}

The file referenced by the getConfigLocations() method (i.e., "classpath:com/foo/daos.xml") looks like this:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" 
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <!-- this bean will be injected into the HibernateTitleDaoTests class -->
    <bean id="titleDao" class="com.foo.dao.hibernate.HibernateTitleDao">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>
    
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <!-- dependencies elided for clarity -->
    </bean>

</beans>

The AbstractDependencyInjectionSpringContextTests classes uses autowire by type. Thus if you have multiple bean definitions of the same type, you cannot rely on this approach for those particular beans. In that case, you can use the inherited applicationContext instance variable and perform explicit lookups using (for example) a call to applicationContext.getBean("titleDao").

If you don't want dependency injection applied to your test cases, simply don't declare any public setter methods. Alternatively, you can extend AbstractSpringContextTests - the root of the JUnit 3.8 integration testing support class hierarchy in the org.springframework.test package - which merely contains convenience methods to load Spring contexts and performs no Dependency Injection of the test fixture.

public final class HibernateTitleDaoTests extends AbstractDependencyInjectionSpringContextTests  {

    public HibernateTitleDaoTests() {
        // switch on field level injection
        setPopulateProtectedVariables(true);
    }

    // this instance will be (automatically) dependency injected
    protected HibernateTitleDao titleDao;

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }

    // specifies the Spring configuration to load for this test fixture
    protected String[] getConfigLocations() {
        return new String[] { "classpath:com/foo/daos.xml" };
    }

}

AbstractTransactionalSpringContextTests depends on a PlatformTransactionManager bean being defined in the application context. The name doesn't matter due to the use of autowire by type.

Typically you will extend the subclass, AbstractTransactionalDataSourceSpringContextTests. This class also requires that a DataSource bean definition - again, with any name - be present in the application context. It creates a JdbcTemplate instance variable, that is useful for convenient querying, and provides handy methods to delete the contents of selected tables (remember that the transaction will roll back by default, so this is safe to do).

If you want a transaction to commit programmatically - unusual, but occasionally useful when you want a particular test to populate the database - you can call the setComplete() method inherited from AbstractTransactionalSpringContextTests. This will cause the transaction to commit instead of roll back. As an alternative, if you are developing against Java 5 or greater and extending AbstractAnnotationAwareTransactionalTests, you may annotate your test method with @Rollback(false) to achieve the same effect through configuration.

There is also the convenient ability to end a transaction before the test case ends, by calling the endTransaction() method. This will roll back the transaction by default and commit it only if setComplete() had previously been called. This functionality is useful if you want to test the behavior of 'disconnected' data objects, such as Hibernate-mapped entities that will be used in a web or remoting tier outside a transaction. Often, lazy loading errors are discovered only through UI testing; if you call endTransaction() you can ensure correct operation of the UI through your JUnit test suite.

When you extend the AbstractTransactionalDataSourceSpringContextTests class you will have access to the following protected instance variables:

The core of the framework consists of the TestContext and TestContextManager classes and the TestExecutionListener interface. A TestContextManager is created on a per-test basis. The TestContextManager in turn manages a TestContext which is responsible for holding the context of the current test. The TestContextManager is also responsible for updating the state of the TestContext as the test progresses and delegating to TestExecutionListeners, which instrument the actual test execution (e.g., providing dependency injection, managing transactions, etc.). Consult the JavaDoc and the Spring test suite for further information and examples of various configurations.

The following three sections explain how to configure the TestContext framework via annotations and provide working examples of how to actually write unit and integration tests with the framework.

Each TestContext provides context management and caching support for the test instance for which it is responsible. Test instances do not automatically receive access to the configured ApplicationContext; however, if a test class implements the ApplicationContextAware interface, a reference to the ApplicationContext will be supplied to the test instance (provided the DependencyInjectionTestExecutionListener has been configured, which is the default). Note that AbstractJUnit38SpringContextTests, AbstractJUnit4SpringContextTests, and AbstractTestNGSpringContextTests already implement ApplicationContextAware and therefore provide this functionality out-of-the-box.

In contrast to the JUnit 3.8 legacy support, test classes which use the TestContext framework do not need to override any protected instance methods to configure their application context. Rather, configuration is achieved merely by declaring the @ContextConfiguration annotation at the class level. If your test class does not explicitly declare any application context resource locations, the configured ContextLoader will determine how and whether or not to load a context from a default set of locations. For example, GenericXmlContextLoader - which is the default ContextLoader - will generate a default location based on the name of the test class. If your class is named com.example.MyTest, GenericXmlContextLoader will load your application context from "classpath:/com/example/MyTest-context.xml".

package com.example;

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from "classpath:/com/example/MyTest-context.xml"
@ContextConfiguration
public class MyTest {
    // class body...
}

If the default location does not suit your needs, you are free to explicitly configure the locations attribute of @ContextConfiguration (see code listing below) with an array containing the resource locations of XML configuration metadata (assuming an XML-capable ContextLoader has been configured) - typically on the classpath - used to configure the application. This will be the same, or nearly the same, as the list of configuration locations specified in web.xml or other deployment configuration. As an alternative you may choose to implement and configure your own custom ContextLoader.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from "/applicationContext.xml" and "/applicationContext-test.xml"
// in the root of the classpath
@ContextConfiguration(locations={"/applicationContext.xml", "/applicationContext-test.xml"})
public class MyTest {
    // class body...
}

@ContextConfiguration also supports a boolean inheritLocations attribute which denotes whether or not resource locations from superclasses should be inherited. The default value is true, which means that an annotated class will inherit the resource locations defined by an annotated superclass. Specifically, the resource locations for an annotated class will be appended to the list of resource locations defined by an annotated superclass. Thus, subclasses have the option of extending the list of resource locations. In the following example, the ApplicationContext for ExtendedTest will be loaded from "/base-context.xml" and "/extended-context.xml", in that order. Beans defined in "/extended-context.xml" may therefore override those defined in "/base-context.xml".

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from "/base-context.xml" in the root of the classpath
@ContextConfiguration(locations={"/base-context.xml"})
public class BaseTest {
    // class body...
}

// ApplicationContext will be loaded from "/base-context.xml" and "/extended-context.xml"
// in the root of the classpath
@ContextConfiguration(locations={"/extended-context.xml"})
public class ExtendedTest extends BaseTest {
    // class body...
}

If inheritLocations is set to false, the resource locations for the annotated class will shadow and effectively replace any resource locations defined by a superclass.

By default, once loaded, the configured ApplicationContext will be reused for each test. Thus the setup cost will be incurred only once (per test fixture), and subsequent test execution will be much faster. In the unlikely case that a test may dirty the application context, requiring reloading - for example, by changing a bean definition or the state of an application object - you may annotate your test method with @DirtiesContext (assuming DirtiesContextTestExecutionListener has been configured, which is the default) to cause the test fixture to reload the configurations and rebuild the application context before executing the next test.

When you configure the DependencyInjectionTestExecutionListener - which is configured by default - via the @TestExecutionListeners annotation, the dependencies of your test instances will be injected from beans in the application context you configured via @ContextConfiguration by Setter Injection, Field Injection, or both, depending on which annotations you choose and whether you place them on setter methods or fields. For consistency with annotation support in Spring 2.5, you may choose either Spring's @Autowired annotation or the @Resource annotation from JSR 250. The semantics for both are consistent throughout the Spring Framework. For example, if you prefer autowiring by type, annotate your setter methods or fields with @Autowired. On the other hand, if you prefer to have your dependencies injected by name, annotate your setter methods or fields with @Resource.

	Tip
	The TestContext framework does not instrument the manner in which a test instance is instantiated. Thus the use of @Autowired for constructors has no effect for test classes.

Since @Autowired performs autowiring by type, if you have multiple bean definitions of the same type, you cannot rely on this approach for those particular beans. In that case, you can use @Resource for injection by name. Alternatively, if your test class implements ApplicationContextAware, you can directly access the ApplicationContext supplied to your test and perform an explicit lookup using (for example) a call to applicationContext.getBean("titleDao").

If you don't want dependency injection applied to your test instances, simply don't annotate any fields or setter methods with @Autowired or @Resource. Alternatively, you can disable dependency injection altogether by explicitly configuring your class with @TestExecutionListeners and omitting DependencyInjectionTestExecutionListener.class from the list of listeners.

Consider the scenario where we have a class, HibernateTitleDao (as outlined in the common goals section). First, let's look at a JUnit 4.4 based implementation of the test class itself which uses @Autowired for field injection (we will look at the application context configuration after all sample code listings). Note: the dependency injection behavior in the following code listings is not in any way specific to JUnit 4.4. The same DI techniques can be used in conjunction with any testing framework.

@RunWith(SpringJUnit4ClassRunner.class)
// specifies the Spring configuration to load for this test fixture
@ContextConfiguration(locations={"daos.xml"})
public final class HibernateTitleDaoTests {

    // this instance will be dependency injected by type
    @Autowired    
    private HibernateTitleDao titleDao;

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }
}

Alternatively, we can configure the class to use @Autowired for setter injection.

@RunWith(SpringJUnit4ClassRunner.class)
// specifies the Spring configuration to load for this test fixture
@ContextConfiguration(locations={"daos.xml"})
public final class HibernateTitleDaoTests {

    // this instance will be dependency injected by type
    private HibernateTitleDao titleDao;

    @Autowired
    public void setTitleDao(HibernateTitleDao titleDao) {
        this.titleDao = titleDao;
    }

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }
}

Now let's take a look at an example using @Resource for field injection.

@RunWith(SpringJUnit4ClassRunner.class)
// specifies the Spring configuration to load for this test fixture
@ContextConfiguration(locations={"daos.xml"})
public final class HibernateTitleDaoTests {

    // this instance will be dependency injected by name
    @Resource
    private HibernateTitleDao titleDao;

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }
}

Finally, here is an example using @Resource for setter injection.

@RunWith(SpringJUnit4ClassRunner.class)
// specifies the Spring configuration to load for this test fixture
@ContextConfiguration(locations={"daos.xml"})
public final class HibernateTitleDaoTests {

    // this instance will be dependency injected by name
    private HibernateTitleDao titleDao;
    
    @Resource
    public void setTitleDao(HibernateTitleDao titleDao) {
        this.titleDao = titleDao;
    }

    public void testLoadTitle() throws Exception {
        Title title = this.titleDao.loadTitle(new Long(10));
        assertNotNull(title);
    }
}

The above code listings use the same XML context file referenced by the @ContextConfiguration annotation (i.e., "daos.xml") which looks like this:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" 
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <!-- this bean will be injected into the HibernateTitleDaoTests class -->
    <bean id="titleDao" class="com.foo.dao.hibernate.HibernateTitleDao">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>
    
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <!-- dependencies elided for clarity -->
    </bean>

</beans>

In the TestContext framework, transactions are managed by the TransactionalTestExecutionListener, which is configured via the @TestExecutionListeners annotation by default, even if you do not explicitly declare @TestExecutionListeners on your test class. To enable support for transactions, however, you must provide a PlatformTransactionManager bean in the application context loaded via @ContextConfiguration semantics. In addition, you must declare @Transactional either at the class or method level.

For class-level transaction configuration (i.e., setting the bean name for the transaction manager and the default rollback flag), see the @TransactionConfiguration entry in the TestContext framework annotation support section.

There are several options for configuring transactions for individual test methods. If transactions are not enabled for the entire test class, methods may be explicitly annotated with @Transactional. Similarly, if transactions are enabled for the entire test class, methods may be explicitly flagged not to run within a transaction by annotating them with @NotTransactional. To control whether or not a transaction should commit for a particular test method, you may use the @Rollback annotation to override the class-level default rollback setting.

Note that AbstractTransactionalJUnit38SpringContextTests, AbstractTransactionalJUnit4SpringContextTests, and AbstractTransactionalTestNGSpringContextTests are pre-configured for transactional support at the class level.

You will occasionally find that you need to execute certain code before or after a transactional test method but outside the transactional context, for example to verify the initial database state prior to execution of your test or to verify expected transactional commit behavior after test execution (e.g., if the test was configured not to roll back the transaction). TransactionalTestExecutionListener supports the @BeforeTransaction and @AfterTransaction annotations exactly for such scenarios. Simply annotate any public void method in your test class with one of these annotations, and the TransactionalTestExecutionListener will ensure that your before transaction method or after transaction method is executed at the appropriate time.

	Tip
	Any before methods (e.g., methods annotated with JUnit 4's @Before) and any after methods (e.g., methods annotated with JUnit 4's @After) will be executed within a transaction. In addition, methods annotated with @BeforeTransaction or @AfterTransaction will naturally not be executed for tests annotated with @NotTransactional.

The following JUnit 4 based example displays a fictitious integration testing scenario highlighting several of the transaction-related annotations. Consult the TestContext framework annotation support section of the reference manual for further information and configuration examples.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
@TransactionConfiguration(transactionManager="txMgr", defaultRollback=false)
@Transactional
public class FictitiousTransactionalTest {

	@BeforeTransaction
	public void verifyInitialDatabaseState() {
		// logic to verify the initial state before a transaction is started
	}

	@Before
	public void setUpTestDataWithinTransaction() {
		// set up test data within the transaction
	}

	@Test
	// overrides the class-level defaultRollback setting
	@Rollback(true)
	public void modifyDatabaseWithinTransaction() {
		// logic which uses the test data and modifies database state
	}

	@After
	public void tearDownWithinTransaction() {
		// execute "tear down" logic within the transaction
	}

	@AfterTransaction
	public void verifyFinalDatabaseState() {
		// logic to verify the final state after transaction has rolled back
	}

	@Test
	@NotTransactional
	public void performNonDatabaseRelatedAction() {
		// logic which does not modify database state
	}
}

The Spring TestContext Framework supports all annotations as outlined in the common annotations section. The following annotations, however, are only supported when used in conjunction with JUnit (e.g., with the SpringJUnit4ClassRunner or the JUnit 3.8 and JUnit 4.4 support classes.

The following non-test-specific annotations are also supported by the Spring TestContext Framework with their standard semantics.

The following list includes all annotations specific to the Spring TestContext Framework. Refer to the respective JavaDoc for further information, including default attribute values, etc.