Custom TestExecutionListeners can be registered for a test class and its subclasses via the @TestExecutionListeners annotation. See annotation support and the javadocs for @TestExecutionListeners for details and examples.

Registering custom TestExecutionListeners via @TestExecutionListeners is suitable for custom listeners that are used in limited testing scenarios; however, it can become cumbersome if a custom listener needs to be used across a test suite. To address this issue, Spring Framework 4.1 supports automatic discovery of default TestExecutionListener implementations via the SpringFactoriesLoader mechanism.

Specifically, the spring-test module declares all core default TestExecutionListeners under the org.springframework.test.context.TestExecutionListener key in its META-INF/spring.factories properties file. Third-party frameworks and developers can contribute their own TestExecutionListeners to the list of default listeners in the same manner via their own META-INF/spring.factories properties file.

When the TestContext framework discovers default TestExecutionListeners via the aforementioned SpringFactoriesLoader mechanism, the instantiated listeners are sorted using Spring’s AnnotationAwareOrderComparator which honors Spring’s Ordered interface and @Order annotation for ordering. AbstractTestExecutionListener and all default TestExecutionListeners provided by Spring implement Ordered with appropriate values. Third-party frameworks and developers should therefore make sure that their default TestExecutionListeners are registered in the proper order by implementing Ordered or declaring @Order. Consult the javadocs for the getOrder() methods of the core default TestExecutionListeners for details on what values are assigned to each core listener.

If a custom TestExecutionListener is registered via @TestExecutionListeners, the default listeners will not be registered. In most common testing scenarios, this effectively forces the developer to manually declare all default listeners in addition to any custom listeners. The following listing demonstrates this style of configuration.

@ContextConfiguration
@TestExecutionListeners({
    MyCustomTestExecutionListener.class,
    ServletTestExecutionListener.class,
    DependencyInjectionTestExecutionListener.class,
    DirtiesContextTestExecutionListener.class,
    TransactionalTestExecutionListener.class,
    SqlScriptsTestExecutionListener.class
})
public class MyTest {
    // class body...
}

The challenge with this approach is that it requires that the developer know exactly which listeners are registered by default. Moreover, the set of default listeners can change from release to release — for example, SqlScriptsTestExecutionListener was introduced in Spring Framework 4.1. Furthermore, third-party frameworks like Spring Security register their own default TestExecutionListeners via the aforementioned automatic discovery mechanism.

To avoid having to be aware of and re-declare all default listeners, the mergeMode attribute of @TestExecutionListeners can be set to MergeMode.MERGE_WITH_DEFAULTS. MERGE_WITH_DEFAULTS indicates that locally declared listeners should be merged with the default listeners. The merging algorithm ensures that duplicates are removed from the list and that the resulting set of merged listeners is sorted according to the semantics of AnnotationAwareOrderComparator as described in the section called “Ordering TestExecutionListeners”. If a listener implements Ordered or is annotated with @Order it can influence the position in which it is merged with the defaults; otherwise, locally declared listeners will simply be appended to the list of default listeners when merged.

For example, if the MyCustomTestExecutionListener class in the previous example configures its order value (for example, 500) to be less than the order of the ServletTestExecutionListener (which happens to be 1000), the MyCustomTestExecutionListener can then be automatically merged with the list of defaults in front of the ServletTestExecutionListener, and the previous example could be replaced with the following.

@ContextConfiguration
@TestExecutionListeners(
    listeners = MyCustomTestExecutionListener.class,
    mergeMode = MERGE_WITH_DEFAULTS,
)
public class MyTest {
    // class body...
}

To load an ApplicationContext for your tests using XML configuration files, annotate your test class with @ContextConfiguration and configure the locations attribute with an array that contains the resource locations of XML configuration metadata. A plain or relative path — for example "context.xml" — will be treated as a classpath resource that is relative to the package in which the test class is defined. A path starting with a slash is treated as an absolute classpath location, for example "/org/example/config.xml". A path which represents a resource URL (i.e., a path prefixed with classpath:, file:, http:, etc.) will be used as is.

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

@ContextConfiguration supports an alias for the locations attribute through the standard Java value attribute. Thus, if you do not need to declare additional attributes in @ContextConfiguration, you can omit the declaration of the locations attribute name and declare the resource locations by using the shorthand format demonstrated in the following example.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration({"/app-config.xml", "/test-config.xml"})
public class MyTest {
    // class body...
}

If you omit both the locations and value attributes from the @ContextConfiguration annotation, the TestContext framework will attempt to detect a default XML resource location. Specifically, GenericXmlContextLoader and GenericXmlWebContextLoader detect a default location based on the name of the test class. If your class is named com.example.MyTest, GenericXmlContextLoader loads 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...
}

To load an ApplicationContext for your tests using Groovy scripts that utilize the Groovy Bean Definition DSL, annotate your test class with @ContextConfiguration and configure the locations or value attribute with an array that contains the resource locations of Groovy scripts. Resource lookup semantics for Groovy scripts are the same as those described for XML configuration files.

	Enabling Groovy script support
	Support for using Groovy scripts to load an ApplicationContext in the Spring TestContext Framework is enabled automatically if Groovy is on the classpath.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from "/AppConfig.groovy" and
// "/TestConfig.groovy" in the root of the classpath
@ContextConfiguration({"/AppConfig.groovy", "/TestConfig.Groovy"})
public class MyTest {
    // class body...
}

If you omit both the locations and value attributes from the @ContextConfiguration annotation, the TestContext framework will attempt to detect a default Groovy script. Specifically, GenericGroovyXmlContextLoader and GenericGroovyXmlWebContextLoader detect a default location based on the name of the test class. If your class is named com.example.MyTest, the Groovy context loader will load your application context from "classpath:com/example/MyTestContext.groovy".

package com.example;

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

Declaring XML config and Groovy scripts simultaneously

Both XML configuration files and Groovy scripts can be declared simultaneously via the locations or value attribute of @ContextConfiguration. If the path to a configured resource location ends with .xml it will be loaded using an XmlBeanDefinitionReader; otherwise it will be loaded using a GroovyBeanDefinitionReader. The following listing demonstrates how to combine both in an integration test. @RunWith(SpringJUnit4ClassRunner.class) // ApplicationContext will be loaded from // "/app-config.xml" and "/TestConfig.groovy" @ContextConfiguration({ "/app-config.xml", "/TestConfig.groovy" }) public class MyTest { // class body... }

To load an ApplicationContext for your tests using annotated classes (see Section 6.12, “Java-based container configuration”), annotate your test class with @ContextConfiguration and configure the classes attribute with an array that contains references to annotated classes.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from AppConfig and TestConfig
@ContextConfiguration(classes = {AppConfig.class, TestConfig.class})
public class MyTest {
    // class body...
}

Annotated Classes

The term annotated class can refer to any of the following. A class annotated with @Configuration A component (i.e., a class annotated with @Component, @Service, @Repository, etc.) A JSR-330 compliant class that is annotated with javax.inject annotations Any other class that contains @Bean-methods Consult the javadocs of @Configuration and @Bean for further information regarding the configuration and semantics of annotated classes, paying special attention to the discussion of `@Bean` Lite Mode.

If you omit the classes attribute from the @ContextConfiguration annotation, the TestContext framework will attempt to detect the presence of default configuration classes. Specifically, AnnotationConfigContextLoader and AnnotationConfigWebContextLoader will detect all static nested classes of the test class that meet the requirements for configuration class implementations as specified in the @Configuration javadocs. In the following example, the OrderServiceTest class declares a static nested configuration class named Config that will be automatically used to load the ApplicationContext for the test class. Note that the name of the configuration class is arbitrary. In addition, a test class can contain more than one static nested configuration class if desired.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from the
// static nested Config class
@ContextConfiguration
public class OrderServiceTest {

    @Configuration
    static class Config {

        // this bean will be injected into the OrderServiceTest class
        @Bean
        public OrderService orderService() {
            OrderService orderService = new OrderServiceImpl();
            // set properties, etc.
            return orderService;
        }
    }

    @Autowired
    private OrderService orderService;

    @Test
    public void testOrderService() {
        // test the orderService
    }

}

It may sometimes be desirable to mix XML configuration files, Groovy scripts, and annotated classes (i.e., typically @Configuration classes) to configure an ApplicationContext for your tests. For example, if you use XML configuration in production, you may decide that you want to use @Configuration classes to configure specific Spring-managed components for your tests, or vice versa.

Furthermore, some third-party frameworks (like Spring Boot) provide first-class support for loading an ApplicationContext from different types of resources simultaneously (e.g., XML configuration files, Groovy scripts, and @Configuration classes). The Spring Framework historically has not supported this for standard deployments. Consequently, most of the SmartContextLoader implementations that the Spring Framework delivers in the spring-test module support only one resource type per test context; however, this does not mean that you cannot use both. One exception to the general rule is that the GenericGroovyXmlContextLoader and GenericGroovyXmlWebContextLoader support both XML configuration files and Groovy scripts simultaneously. Furthermore, third-party frameworks may choose to support the declaration of both locations and classes via @ContextConfiguration, and with the standard testing support in the TestContext framework, you have the following options.

If you want to use resource locations (e.g., XML or Groovy) and @Configuration classes to configure your tests, you will have to pick one as the entry point, and that one will have to include or import the other. For example, in XML or Groovy scripts you can include @Configuration classes via component scanning or define them as normal Spring beans; whereas, in a @Configuration class you can use @ImportResource to import XML configuration files. Note that this behavior is semantically equivalent to how you configure your application in production: in production configuration you will define either a set of XML or Groovy resource locations or a set of @Configuration classes that your production ApplicationContext will be loaded from, but you still have the freedom to include or import the other type of configuration.

To configure an ApplicationContext for your tests using context initializers, annotate your test class with @ContextConfiguration and configure the initializers attribute with an array that contains references to classes that implement ApplicationContextInitializer. The declared context initializers will then be used to initialize the ConfigurableApplicationContext that is loaded for your tests. Note that the concrete ConfigurableApplicationContext type supported by each declared initializer must be compatible with the type of ApplicationContext created by the SmartContextLoader in use (i.e., typically a GenericApplicationContext). Furthermore, the order in which the initializers are invoked depends on whether they implement Spring’s Ordered interface, are annotated with Spring’s @Order or the standard @Priority annotation.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from TestConfig
// and initialized by TestAppCtxInitializer
@ContextConfiguration(
    classes = TestConfig.class,
    initializers = TestAppCtxInitializer.class)
public class MyTest {
    // class body...
}

It is also possible to omit the declaration of XML configuration files or annotated classes in @ContextConfiguration entirely and instead declare only ApplicationContextInitializer classes which are then responsible for registering beans in the context — for example, by programmatically loading bean definitions from XML files or configuration classes.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be initialized by EntireAppInitializer
// which presumably registers beans in the context
@ContextConfiguration(initializers = EntireAppInitializer.class)
public class MyTest {
    // class body...
}

@ContextConfiguration supports boolean inheritLocations and inheritInitializers attributes that denote whether resource locations or annotated classes and context initializers declared by superclasses should be inherited. The default value for both flags is true. This means that a test class inherits the resource locations or annotated classes as well as the context initializers declared by any superclasses. Specifically, the resource locations or annotated classes for a test class are appended to the list of resource locations or annotated classes declared by superclasses. Similarly, the initializers for a given test class will be added to the set of initializers defined by test superclasses. Thus, subclasses have the option of extending the resource locations, annotated classes, or context initializers.

If the inheritLocations or inheritInitializers attribute in @ContextConfiguration is set to false, the resource locations or annotated classes and the context initializers, respectively, for the test class shadow and effectively replace the configuration defined by superclasses.

In the following example that uses XML resource locations, the ApplicationContext for ExtendedTest will be loaded from "base-config.xml" and "extended-config.xml", in that order. Beans defined in "extended-config.xml" may therefore override (i.e., replace) those defined in "base-config.xml".

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

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

Similarly, in the following example that uses annotated classes, the ApplicationContext for ExtendedTest will be loaded from the BaseConfig and ExtendedConfig classes, in that order. Beans defined in ExtendedConfig may therefore override (i.e., replace) those defined in BaseConfig.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from BaseConfig
@ContextConfiguration(classes = BaseConfig.class)
public class BaseTest {
    // class body...
}

// ApplicationContext will be loaded from BaseConfig and ExtendedConfig
@ContextConfiguration(classes = ExtendedConfig.class)
public class ExtendedTest extends BaseTest {
    // class body...
}

In the following example that uses context initializers, the ApplicationContext for ExtendedTest will be initialized using BaseInitializer and ExtendedInitializer. Note, however, that the order in which the initializers are invoked depends on whether they implement Spring’s Ordered interface, are annotated with Spring’s @Order or the standard @Priority annotation.

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be initialized by BaseInitializer
@ContextConfiguration(initializers = BaseInitializer.class)
public class BaseTest {
    // class body...
}

// ApplicationContext will be initialized by BaseInitializer
// and ExtendedInitializer
@ContextConfiguration(initializers = ExtendedInitializer.class)
public class ExtendedTest extends BaseTest {
    // class body...
}

Spring 3.1 introduced first-class support in the framework for the notion of environments and profiles (a.k.a., bean definition profiles), and integration tests can be configured to activate particular bean definition profiles for various testing scenarios. This is achieved by annotating a test class with the @ActiveProfiles annotation and supplying a list of profiles that should be activated when loading the ApplicationContext for the test.

	Note
	@ActiveProfiles may be used with any implementation of the new SmartContextLoader SPI, but @ActiveProfiles is not supported with implementations of the older ContextLoader SPI.

Let’s take a look at some examples with XML configuration and @Configuration classes.

<!-- app-config.xml -->
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:jdbc="http://www.springframework.org/schema/jdbc"
    xmlns:jee="http://www.springframework.org/schema/jee"
    xsi:schemaLocation="...">

    <bean id="transferService"
            class="com.bank.service.internal.DefaultTransferService">
        <constructor-arg ref="accountRepository"/>
        <constructor-arg ref="feePolicy"/>
    </bean>

    <bean id="accountRepository"
            class="com.bank.repository.internal.JdbcAccountRepository">
        <constructor-arg ref="dataSource"/>
    </bean>

    <bean id="feePolicy"
        class="com.bank.service.internal.ZeroFeePolicy"/>

    <beans profile="dev">
        <jdbc:embedded-database id="dataSource">
            <jdbc:script
                location="classpath:com/bank/config/sql/schema.sql"/>
            <jdbc:script
                location="classpath:com/bank/config/sql/test-data.sql"/>
        </jdbc:embedded-database>
    </beans>

    <beans profile="production">
        <jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/datasource"/>
    </beans>

    <beans profile="default">
        <jdbc:embedded-database id="dataSource">
            <jdbc:script
                location="classpath:com/bank/config/sql/schema.sql"/>
        </jdbc:embedded-database>
    </beans>

</beans>

package com.bank.service;

@RunWith(SpringJUnit4ClassRunner.class)
// ApplicationContext will be loaded from "classpath:/app-config.xml"
@ContextConfiguration("/app-config.xml")
@ActiveProfiles("dev")
public class TransferServiceTest {

    @Autowired
    private TransferService transferService;

    @Test
    public void testTransferService() {
        // test the transferService
    }
}

When TransferServiceTest is run, its ApplicationContext will be loaded from the app-config.xml configuration file in the root of the classpath. If you inspect app-config.xml you’ll notice that the accountRepository bean has a dependency on a dataSource bean; however, dataSource is not defined as a top-level bean. Instead, dataSource is defined three times: in the production profile, the dev profile, and the default profile.

By annotating TransferServiceTest with @ActiveProfiles("dev") we instruct the Spring TestContext Framework to load the ApplicationContext with the active profiles set to {"dev"}. As a result, an embedded database will be created and populated with test data, and the accountRepository bean will be wired with a reference to the development DataSource. And that’s likely what we want in an integration test.

It is sometimes useful to assign beans to a default profile. Beans within the default profile are only included when no other profile is specifically activated. This can be used to define fallback beans to be used in the application’s default state. For example, you may explicitly provide a data source for dev and production profiles, but define an in-memory data source as a default when neither of these is active.

The following code listings demonstrate how to implement the same configuration and integration test but using @Configuration classes instead of XML.

@Configuration
@Profile("dev")
public class StandaloneDataConfig {

    @Bean
    public DataSource dataSource() {
        return new EmbeddedDatabaseBuilder()
            .setType(EmbeddedDatabaseType.HSQL)
            .addScript("classpath:com/bank/config/sql/schema.sql")
            .addScript("classpath:com/bank/config/sql/test-data.sql")
            .build();
    }
}

@Configuration
@Profile("production")
public class JndiDataConfig {

    @Bean(destroyMethod="")
    public DataSource dataSource() throws Exception {
        Context ctx = new InitialContext();
        return (DataSource) ctx.lookup("java:comp/env/jdbc/datasource");
    }
}

@Configuration
@Profile("default")
public class DefaultDataConfig {

    @Bean
    public DataSource dataSource() {
        return new EmbeddedDatabaseBuilder()
            .setType(EmbeddedDatabaseType.HSQL)
            .addScript("classpath:com/bank/config/sql/schema.sql")
            .build();
    }
}

@Configuration
public class TransferServiceConfig {

    @Autowired DataSource dataSource;

    @Bean
    public TransferService transferService() {
        return new DefaultTransferService(accountRepository(), feePolicy());
    }

    @Bean
    public AccountRepository accountRepository() {
        return new JdbcAccountRepository(dataSource);
    }

    @Bean
    public FeePolicy feePolicy() {
        return new ZeroFeePolicy();
    }

}

package com.bank.service;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {
        TransferServiceConfig.class,
        StandaloneDataConfig.class,
        JndiDataConfig.class,
        DefaultDataConfig.class})
@ActiveProfiles("dev")
public class TransferServiceTest {

    @Autowired
    private TransferService transferService;

    @Test
    public void testTransferService() {
        // test the transferService
    }
}

In this variation, we have split the XML configuration into four independent @Configuration classes:

As with the XML-based configuration example, we still annotate TransferServiceTest with @ActiveProfiles("dev"), but this time we specify all four configuration classes via the @ContextConfiguration annotation. The body of the test class itself remains completely unchanged.

It is often the case that a single set of profiles is used across multiple test classes within a given project. Thus, to avoid duplicate declarations of the @ActiveProfiles annotation it is possible to declare @ActiveProfiles once on a base class, and subclasses will automatically inherit the @ActiveProfiles configuration from the base class. In the following example, the declaration of @ActiveProfiles (as well as other annotations) has been moved to an abstract superclass, AbstractIntegrationTest.

package com.bank.service;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {
        TransferServiceConfig.class,
        StandaloneDataConfig.class,
        JndiDataConfig.class,
        DefaultDataConfig.class})
@ActiveProfiles("dev")
public abstract class AbstractIntegrationTest {
}

package com.bank.service;

// "dev" profile inherited from superclass
public class TransferServiceTest extends AbstractIntegrationTest {

    @Autowired
    private TransferService transferService;

    @Test
    public void testTransferService() {
        // test the transferService
    }
}

@ActiveProfiles also supports an inheritProfiles attribute that can be used to disable the inheritance of active profiles.

package com.bank.service;

// "dev" profile overridden with "production"
@ActiveProfiles(profiles = "production", inheritProfiles = false)
public class ProductionTransferServiceTest extends AbstractIntegrationTest {
    // test body
}

Furthermore, it is sometimes necessary to resolve active profiles for tests programmatically instead of declaratively — for example, based on:

To resolve active bean definition profiles programmatically, simply implement a custom ActiveProfilesResolver and register it via the resolver attribute of @ActiveProfiles. The following example demonstrates how to implement and register a custom OperatingSystemActiveProfilesResolver. For further information, refer to the corresponding javadocs.

package com.bank.service;

// "dev" profile overridden programmatically via a custom resolver
@ActiveProfiles(
    resolver = OperatingSystemActiveProfilesResolver.class,
    inheritProfiles = false)
public class TransferServiceTest extends AbstractIntegrationTest {
    // test body
}

package com.bank.service.test;

public class OperatingSystemActiveProfilesResolver implements ActiveProfilesResolver {

    @Override
    String[] resolve(Class<?> testClass) {
        String profile = ...;
        // determine the value of profile based on the operating system
        return new String[] {profile};
    }
}

Spring 3.1 introduced first-class support in the framework for the notion of an environment with a hierarchy of property sources, and since Spring 4.1 integration tests can be configured with test-specific property sources. In contrast to the @PropertySource annotation used on @Configuration classes, the @TestPropertySource annotation can be declared on a test class to declare resource locations for test properties files or inlined properties. These test property sources will be added to the set of PropertySources in the Environment for the ApplicationContext loaded for the annotated integration test.

	Note
	@TestPropertySource may be used with any implementation of the SmartContextLoader SPI, but @TestPropertySource is not supported with implementations of the older ContextLoader SPI. Implementations of SmartContextLoader gain access to merged test property source values via the getPropertySourceLocations() and getPropertySourceProperties() methods in MergedContextConfiguration.

Declaring test property sources

Test properties files can be configured via the locations or value attribute of @TestPropertySource as shown in the following example.

Both traditional and XML-based properties file formats are supported — for example, "classpath:/com/example/test.properties" or "file:///path/to/file.xml".

Each path will be interpreted as a Spring Resource. A plain path — for example, "test.properties" — will be treated as a classpath resource that is relative to the package in which the test class is defined. A path starting with a slash will be treated as an absolute classpath resource, for example: "/org/example/test.xml". A path which references a URL (e.g., a path prefixed with classpath:, file:, http:, etc.) will be loaded using the specified resource protocol. Resource location wildcards (e.g. */.properties) are not permitted: each location must evaluate to exactly one .properties or .xml resource.

@ContextConfiguration
@TestPropertySource("/test.properties")
public class MyIntegrationTests {
    // class body...
}

Inlined properties in the form of key-value pairs can be configured via the properties attribute of @TestPropertySource as shown in the following example. All key-value pairs will be added to the enclosing Environment as a single test PropertySource with the highest precedence.

The supported syntax for key-value pairs is the same as the syntax defined for entries in a Java properties file:

@ContextConfiguration
@TestPropertySource(properties = {"timezone = GMT", "port: 4242"})
public class MyIntegrationTests {
    // class body...
}

Default properties file detection

If @TestPropertySource is declared as an empty annotation (i.e., without explicit values for the locations or properties attributes), an attempt will be made to detect a default properties file relative to the class that declared the annotation. For example, if the annotated test class is com.example.MyTest, the corresponding default properties file is "classpath:com/example/MyTest.properties". If the default cannot be detected, an IllegalStateException will be thrown.

Precedence

Test property sources have higher precedence than those loaded from the operating system’s environment or Java system properties as well as property sources added by the application declaratively via @PropertySource or programmatically. Thus, test property sources can be used to selectively override properties defined in system and application property sources. Furthermore, inlined properties have higher precedence than properties loaded from resource locations.

In the following example, the timezone and port properties as well as any properties defined in "/test.properties" will override any properties of the same name that are defined in system and application property sources. Furthermore, if the "/test.properties" file defines entries for the timezone and port properties those will be overridden by the inlined properties declared via the properties attribute.

@ContextConfiguration
@TestPropertySource(
    locations = "/test.properties",
    properties = {"timezone = GMT", "port: 4242"}
)
public class MyIntegrationTests {
    // class body...
}

Inheriting and overriding test property sources

@TestPropertySource supports boolean inheritLocations and inheritProperties attributes that denote whether resource locations for properties files and inlined properties declared by superclasses should be inherited. The default value for both flags is true. This means that a test class inherits the locations and inlined properties declared by any superclasses. Specifically, the locations and inlined properties for a test class are appended to the locations and inlined properties declared by superclasses. Thus, subclasses have the option of extending the locations and inlined properties. Note that properties that appear later will shadow (i.e.., override) properties of the same name that appear earlier. In addition, the aforementioned precedence rules apply for inherited test property sources as well.

If the inheritLocations or inheritProperties attribute in @TestPropertySource is set to false, the locations or inlined properties, respectively, for the test class shadow and effectively replace the configuration defined by superclasses.

In the following example, the ApplicationContext for BaseTest will be loaded using only the "base.properties" file as a test property source. In contrast, the ApplicationContext for ExtendedTest will be loaded using the "base.properties" and "extended.properties" files as test property source locations.

@TestPropertySource("base.properties")
@ContextConfiguration
public class BaseTest {
    // ...
}

@TestPropertySource("extended.properties")
@ContextConfiguration
public class ExtendedTest extends BaseTest {
    // ...
}

In the following example, the ApplicationContext for BaseTest will be loaded using only the inlined key1 property. In contrast, the ApplicationContext for ExtendedTest will be loaded using the inlined key1 and key2 properties.

@TestPropertySource(properties = "key1 = value1")
@ContextConfiguration
public class BaseTest {
    // ...
}

@TestPropertySource(properties = "key2 = value2")
@ContextConfiguration
public class ExtendedTest extends BaseTest {
    // ...
}

Spring 3.2 introduced support for loading a WebApplicationContext in integration tests. To instruct the TestContext framework to load a WebApplicationContext instead of a standard ApplicationContext, simply annotate the respective test class with @WebAppConfiguration.

The presence of @WebAppConfiguration on your test class instructs the TestContext framework (TCF) that a WebApplicationContext (WAC) should be loaded for your integration tests. In the background the TCF makes sure that a MockServletContext is created and supplied to your test’s WAC. By default the base resource path for your MockServletContext will be set to "src/main/webapp". This is interpreted as a path relative to the root of your JVM (i.e., normally the path to your project). If you’re familiar with the directory structure of a web application in a Maven project, you’ll know that "src/main/webapp" is the default location for the root of your WAR. If you need to override this default, simply provide an alternate path to the @WebAppConfiguration annotation (e.g., @WebAppConfiguration("src/test/webapp")). If you wish to reference a base resource path from the classpath instead of the file system, just use Spring’s classpath: prefix.

Please note that Spring’s testing support for WebApplicationContexts is on par with its support for standard ApplicationContexts. When testing with a WebApplicationContext you are free to declare XML configuration files, Groovy scripts, or @Configuration classes via @ContextConfiguration. You are of course also free to use any other test annotations such as @ActiveProfiles, @TestExecutionListeners, @Sql, @Rollback, etc.

The following examples demonstrate some of the various configuration options for loading a WebApplicationContext.

Conventions. 

@RunWith(SpringJUnit4ClassRunner.class)

// defaults to "file:src/main/webapp"
@WebAppConfiguration

// detects "WacTests-context.xml" in same package
// or static nested @Configuration class
@ContextConfiguration

public class WacTests {
    //...
}

The above example demonstrates the TestContext framework’s support for convention over configuration. If you annotate a test class with @WebAppConfiguration without specifying a resource base path, the resource path will effectively default to "file:src/main/webapp". Similarly, if you declare @ContextConfiguration without specifying resource locations, annotated classes, or context initializers, Spring will attempt to detect the presence of your configuration using conventions (i.e., "WacTests-context.xml" in the same package as the WacTests class or static nested @Configuration classes).

Default resource semantics. 

@RunWith(SpringJUnit4ClassRunner.class)

// file system resource
@WebAppConfiguration("webapp")

// classpath resource
@ContextConfiguration("/spring/test-servlet-config.xml")

public class WacTests {
    //...
}

This example demonstrates how to explicitly declare a resource base path with @WebAppConfiguration and an XML resource location with @ContextConfiguration. The important thing to note here is the different semantics for paths with these two annotations. By default, @WebAppConfiguration resource paths are file system based; whereas, @ContextConfiguration resource locations are classpath based.

Explicit resource semantics. 

@RunWith(SpringJUnit4ClassRunner.class)

// classpath resource
@WebAppConfiguration("classpath:test-web-resources")

// file system resource
@ContextConfiguration("file:src/main/webapp/WEB-INF/servlet-config.xml")

public class WacTests {
    //...
}

In this third example, we see that we can override the default resource semantics for both annotations by specifying a Spring resource prefix. Contrast the comments in this example with the previous example.

To provide comprehensive web testing support, Spring 3.2 introduced a ServletTestExecutionListener that is enabled by default. When testing against a WebApplicationContext this TestExecutionListener sets up default thread-local state via Spring Web’s RequestContextHolder before each test method and creates a MockHttpServletRequest, MockHttpServletResponse, and ServletWebRequest based on the base resource path configured via @WebAppConfiguration. ServletTestExecutionListener also ensures that the MockHttpServletResponse and ServletWebRequest can be injected into the test instance, and once the test is complete it cleans up thread-local state.

Once you have a WebApplicationContext loaded for your test you might find that you need to interact with the web mocks — for example, to set up your test fixture or to perform assertions after invoking your web component. The following example demonstrates which mocks can be autowired into your test instance. Note that the WebApplicationContext and MockServletContext are both cached across the test suite; whereas, the other mocks are managed per test method by the ServletTestExecutionListener.

Injecting mocks. 

@WebAppConfiguration
@ContextConfiguration
public class WacTests {

    @Autowired
    WebApplicationContext wac; // cached

    @Autowired
    MockServletContext servletContext; // cached

    @Autowired
    MockHttpSession session;

    @Autowired
    MockHttpServletRequest request;

    @Autowired
    MockHttpServletResponse response;

    @Autowired
    ServletWebRequest webRequest;

    //...
}

Once the TestContext framework loads an ApplicationContext (or WebApplicationContext) for a test, that context will be cached and reused for all subsequent tests that declare the same unique context configuration within the same test suite. To understand how caching works, it is important to understand what is meant by unique and test suite.

An ApplicationContext can be uniquely identified by the combination of configuration parameters that are used to load it. Consequently, the unique combination of configuration parameters are used to generate a key under which the context is cached. The TestContext framework uses the following configuration parameters to build the context cache key:

For example, if TestClassA specifies {"app-config.xml", "test-config.xml"} for the locations (or value) attribute of @ContextConfiguration, the TestContext framework will load the corresponding ApplicationContext and store it in a static context cache under a key that is based solely on those locations. So if TestClassB also defines {"app-config.xml", "test-config.xml"} for its locations (either explicitly or implicitly through inheritance) but does not define @WebAppConfiguration, a different ContextLoader, different active profiles, different context initializers, different test property sources, or a different parent context, then the same ApplicationContext will be shared by both test classes. This means that the setup cost for loading an application context is incurred only once (per test suite), and subsequent test execution is much faster.

Test suites and forked processes

The Spring TestContext framework stores application contexts in a static cache. This means that the context is literally stored in a static variable. In other words, if tests execute in separate processes the static cache will be cleared between each test execution, and this will effectively disable the caching mechanism. To benefit from the caching mechanism, all tests must run within the same process or test suite. This can be achieved by executing all tests as a group within an IDE. Similarly, when executing tests with a build framework such as Ant, Maven, or Gradle it is important to make sure that the build framework does not fork between tests. For example, if the forkMode for the Maven Surefire plug-in is set to always or pertest, the TestContext framework will not be able to cache application contexts between test classes and the build process will run significantly slower as a result.

Since having a large number of application contexts loaded within a given test suite can cause the suite to take an unnecessarily long time to execute, it is often beneficial to know exactly how many contexts have been loaded and cached. To view the statistics for the underlying context cache, simply set the log level for the org.springframework.test.context.cache logging category to DEBUG.

In the unlikely case that a test corrupts the application context and requires reloading — for example, by modifying a bean definition or the state of an application object — you can annotate your test class or test method with @DirtiesContext (see the discussion of @DirtiesContext in Section 14.4.1, “Spring Testing Annotations”). This instructs Spring to remove the context from the cache and rebuild the application context before executing the next test. Note that support for the @DirtiesContext annotation is provided by the DirtiesContextTestExecutionListener which is enabled by default.

When writing integration tests that rely on a loaded Spring ApplicationContext, it is often sufficient to test against a single context; however, there are times when it is beneficial or even necessary to test against a hierarchy of ApplicationContexts. For example, if you are developing a Spring MVC web application you will typically have a root WebApplicationContext loaded via Spring’s ContextLoaderListener and a child WebApplicationContext loaded via Spring’s DispatcherServlet. This results in a parent-child context hierarchy where shared components and infrastructure configuration are declared in the root context and consumed in the child context by web-specific components. Another use case can be found in Spring Batch applications where you often have a parent context that provides configuration for shared batch infrastructure and a child context for the configuration of a specific batch job.

As of Spring Framework 3.2.2, it is possible to write integration tests that use context hierarchies by declaring context configuration via the @ContextHierarchy annotation, either on an individual test class or within a test class hierarchy. If a context hierarchy is declared on multiple classes within a test class hierarchy it is also possible to merge or override the context configuration for a specific, named level in the context hierarchy. When merging configuration for a given level in the hierarchy the configuration resource type (i.e., XML configuration files or annotated classes) must be consistent; otherwise, it is perfectly acceptable to have different levels in a context hierarchy configured using different resource types.

The following JUnit-based examples demonstrate common configuration scenarios for integration tests that require the use of context hierarchies.

ControllerIntegrationTests represents a typical integration testing scenario for a Spring MVC web application by declaring a context hierarchy consisting of two levels, one for the root WebApplicationContext (loaded using the TestAppConfig @Configuration class) and one for the dispatcher servlet WebApplicationContext (loaded using the WebConfig @Configuration class). The WebApplicationContext that is autowired into the test instance is the one for the child context (i.e., the lowest context in the hierarchy).

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextHierarchy({
    @ContextConfiguration(classes = TestAppConfig.class),
    @ContextConfiguration(classes = WebConfig.class)
})
public class ControllerIntegrationTests {

    @Autowired
    private WebApplicationContext wac;

    // ...
}

The following test classes define a context hierarchy within a test class hierarchy. AbstractWebTests declares the configuration for a root WebApplicationContext in a Spring-powered web application. Note, however, that AbstractWebTests does not declare @ContextHierarchy; consequently, subclasses of AbstractWebTests can optionally participate in a context hierarchy or simply follow the standard semantics for @ContextConfiguration. SoapWebServiceTests and RestWebServiceTests both extend AbstractWebTests and define a context hierarchy via @ContextHierarchy. The result is that three application contexts will be loaded (one for each declaration of @ContextConfiguration), and the application context loaded based on the configuration in AbstractWebTests will be set as the parent context for each of the contexts loaded for the concrete subclasses.

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration("file:src/main/webapp/WEB-INF/applicationContext.xml")
public abstract class AbstractWebTests {}

@ContextHierarchy(@ContextConfiguration("/spring/soap-ws-config.xml")
public class SoapWebServiceTests extends AbstractWebTests {}

@ContextHierarchy(@ContextConfiguration("/spring/rest-ws-config.xml")
public class RestWebServiceTests extends AbstractWebTests {}

The following classes demonstrate the use of named hierarchy levels in order to merge the configuration for specific levels in a context hierarchy. BaseTests defines two levels in the hierarchy, parent and child. ExtendedTests extends BaseTests and instructs the Spring TestContext Framework to merge the context configuration for the child hierarchy level, simply by ensuring that the names declared via the name attribute in @ContextConfiguration are both "child". The result is that three application contexts will be loaded: one for "/app-config.xml", one for "/user-config.xml", and one for {"/user-config.xml", "/order-config.xml"}. As with the previous example, the application context loaded from "/app-config.xml" will be set as the parent context for the contexts loaded from "/user-config.xml" and {"/user-config.xml", "/order-config.xml"}.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextHierarchy({
    @ContextConfiguration(name = "parent", locations = "/app-config.xml"),
    @ContextConfiguration(name = "child", locations = "/user-config.xml")
})
public class BaseTests {}

@ContextHierarchy(
    @ContextConfiguration(name = "child", locations = "/order-config.xml")
)
public class ExtendedTests extends BaseTests {}

In contrast to the previous example, this example demonstrates how to override the configuration for a given named level in a context hierarchy by setting the inheritLocations flag in @ContextConfiguration to false. Consequently, the application context for ExtendedTests will be loaded only from "/test-user-config.xml" and will have its parent set to the context loaded from "/app-config.xml".

@RunWith(SpringJUnit4ClassRunner.class)
@ContextHierarchy({
    @ContextConfiguration(name = "parent", locations = "/app-config.xml"),
    @ContextConfiguration(name = "child", locations = "/user-config.xml")
})
public class BaseTests {}

@ContextHierarchy(
    @ContextConfiguration(
        name = "child",
        locations = "/test-user-config.xml",
        inheritLocations = false
))
public class ExtendedTests extends BaseTests {}

	Dirtying a context within a context hierarchy
	If @DirtiesContext is used in a test whose context is configured as part of a context hierarchy, the hierarchyMode flag can be used to control how the context cache is cleared. For further details consult the discussion of @DirtiesContext in Spring Testing Annotations and the @DirtiesContext javadocs.

Test-managed transactions are transactions that are managed declaratively via the TransactionalTestExecutionListener or programmatically via TestTransaction (see below). Such transactions should not be confused with Spring-managed transactions (i.e., those managed directly by Spring within the ApplicationContext loaded for tests) or application-managed transactions (i.e., those managed programmatically within application code that is invoked via tests). Spring-managed and application-managed transactions will typically participate in test-managed transactions; however, caution should be taken if Spring-managed or application-managed transactions are configured with any propagation type other than REQUIRED or SUPPORTS (see the discussion on transaction propagation for details).

Annotating a test method with @Transactional causes the test to be run within a transaction that will, by default, be automatically rolled back after completion of the test. If a test class is annotated with @Transactional, each test method within that class hierarchy will be run within a transaction. Test methods that are not annotated with @Transactional (at the class or method level) will not be run within a transaction. Furthermore, tests that are annotated with @Transactional but have the propagation type set to NOT_SUPPORTED will not be run within a transaction.

Note that AbstractTransactionalJUnit4SpringContextTests and AbstractTransactionalTestNGSpringContextTests are preconfigured for transactional support at the class level.

The following example demonstrates a common scenario for writing an integration test for a Hibernate-based UserRepository. As explained in the section called “Transaction rollback and commit behavior”, there is no need to clean up the database after the createUser() method is executed since any changes made to the database will be automatically rolled back by the TransactionalTestExecutionListener. See Section 14.7, “PetClinic Example” for an additional example.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = TestConfig.class)
@Transactional
public class HibernateUserRepositoryTests {

    @Autowired
    HibernateUserRepository repository;

    @Autowired
    SessionFactory sessionFactory;

    JdbcTemplate jdbcTemplate;

    @Autowired
    public void setDataSource(DataSource dataSource) {
        this.jdbcTemplate = new JdbcTemplate(dataSource);
    }

    @Test
    public void createUser() {
        // track initial state in test database:
        final int count = countRowsInTable("user");

        User user = new User(...);
        repository.save(user);

        // Manual flush is required to avoid false positive in test
        sessionFactory.getCurrentSession().flush();
        assertNumUsers(count + 1);
    }

    protected int countRowsInTable(String tableName) {
        return JdbcTestUtils.countRowsInTable(this.jdbcTemplate, tableName);
    }

    protected void assertNumUsers(int expected) {
        assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"));
    }
}

By default, test transactions will be automatically rolled back after completion of the test; however, transactional commit and rollback behavior can be configured declaratively via the @Rollback annotation. See the corresponding entry in the annotation support section for further details.

As of Spring Framework 4.1, it is possible to interact with test-managed transactions programmatically via the static methods in TestTransaction. For example, TestTransaction may be used within test methods, before methods, and after methods to start or end the current test-managed transaction or to configure the current test-managed transaction for rollback or commit. Support for TestTransaction is automatically available whenever the TransactionalTestExecutionListener is enabled.

The following example demonstrates some of the features of TestTransaction. Consult the javadocs for TestTransaction for further details.

@ContextConfiguration(classes = TestConfig.class)
public class ProgrammaticTransactionManagementTests extends
        AbstractTransactionalJUnit4SpringContextTests {

    @Test
    public void transactionalTest() {
        // assert initial state in test database:
        assertNumUsers(2);

        deleteFromTables("user");

        // changes to the database will be committed!
        TestTransaction.flagForCommit();
        TestTransaction.end();
        assertFalse(TestTransaction.isActive());
        assertNumUsers(0);

        TestTransaction.start();
        // perform other actions against the database that will
        // be automatically rolled back after the test completes...
    }

    protected void assertNumUsers(int expected) {
        assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"));
    }
}

Occasionally 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 (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 ensures that your before transaction method or after transaction method is executed at the appropriate time.

	Tip
	Any before methods (such as methods annotated with JUnit’s @Before) and any after methods (such as methods annotated with JUnit’s @After) are executed within a transaction. In addition, methods annotated with @BeforeTransaction or @AfterTransaction are naturally not executed for test methods that are not configured to run within a transaction.

TransactionalTestExecutionListener expects a PlatformTransactionManager bean to be defined in the Spring ApplicationContext for the test. In case there are multiple instances of PlatformTransactionManager within the test’s ApplicationContext, a qualifier may be declared via @Transactional("myTxMgr") or @Transactional(transactionManager = "myTxMgr"), or TransactionManagementConfigurer can be implemented by an @Configuration class. Consult the javadocs for TestContextTransactionUtils.retrieveTransactionManager() for details on the algorithm used to look up a transaction manager in the test’s ApplicationContext.

The following JUnit-based example displays a fictitious integration testing scenario highlighting all transaction-related annotations. The example is not intended to demonstrate best practices but rather to demonstrate how these annotations can be used. Consult the annotation support section for further information and configuration examples. Transaction management for @Sql contains an additional example using @Sql for declarative SQL script execution with default transaction rollback semantics.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
@Transactional(transactionManager = "txMgr")
@Rollback(false)
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 default rollback 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
    }

}

Avoid false positives when testing ORM code

When you test application code that manipulates the state of the Hibernate session, make sure to flush the underlying session within test methods that execute that code. Failing to flush the underlying session can produce false positives: your test may pass, but the same code throws an exception in a live, production environment. In the following Hibernate-based example test case, one method demonstrates a false positive, and the other method correctly exposes the results of flushing the session. Note that this applies to JPA and any other ORM frameworks that maintain an in-memory unit of work. // ... @Autowired private SessionFactory sessionFactory; @Test // no expected exception! public void falsePositive() { updateEntityInHibernateSession(); // False positive: an exception will be thrown once the session is // finally flushed (i.e., in production code) } @Test(expected = GenericJDBCException.class) public void updateWithSessionFlush() { updateEntityInHibernateSession(); // Manual flush is required to avoid false positive in test sessionFactory.getCurrentSession().flush(); } // ...

Spring provides the following options for executing SQL scripts programmatically within integration test methods.

ScriptUtils provides a collection of static utility methods for working with SQL scripts and is mainly intended for internal use within the framework. However, if you require full control over how SQL scripts are parsed and executed, ScriptUtils may suit your needs better than some of the other alternatives described below. Consult the javadocs for individual methods in ScriptUtils for further details.

ResourceDatabasePopulator provides a simple object-based API for programmatically populating, initializing, or cleaning up a database using SQL scripts defined in external resources. ResourceDatabasePopulator provides options for configuring the character encoding, statement separator, comment delimiters, and error handling flags used when parsing and executing the scripts, and each of the configuration options has a reasonable default value. Consult the javadocs for details on default values. To execute the scripts configured in a ResourceDatabasePopulator, you can invoke either the populate(Connection) method to execute the populator against a java.sql.Connection or the execute(DataSource) method to execute the populator against a javax.sql.DataSource. The following example specifies SQL scripts for a test schema and test data, sets the statement separator to "@@", and then executes the scripts against a DataSource.

@Test
public void databaseTest {
    ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
    populator.addScripts(
        new ClassPathResource("test-schema.sql"),
        new ClassPathResource("test-data.sql"));
    populator.setSeparator("@@");
    populator.execute(this.dataSource);
    // execute code that uses the test schema and data
}

Note that ResourceDatabasePopulator internally delegates to ScriptUtils for parsing and executing SQL scripts. Similarly, the executeSqlScript(..) methods in AbstractTransactionalJUnit4SpringContextTests and AbstractTransactionalTestNGSpringContextTests internally use a ResourceDatabasePopulator for executing SQL scripts. Consult the javadocs for the various executeSqlScript(..) methods for further details.

In addition to the aforementioned mechanisms for executing SQL scripts programmatically, SQL scripts can also be configured declaratively in the Spring TestContext Framework. Specifically, the @Sql annotation can be declared on a test class or test method to configure the resource paths to SQL scripts that should be executed against a given database either before or after an integration test method. Note that method-level declarations override class-level declarations and that support for @Sql is provided by the SqlScriptsTestExecutionListener which is enabled by default.

Path resource semantics

Each path will be interpreted as a Spring Resource. A plain path — for example, "schema.sql" — will be treated as a classpath resource that is relative to the package in which the test class is defined. A path starting with a slash will be treated as an absolute classpath resource, for example: "/org/example/schema.sql". A path which references a URL (e.g., a path prefixed with classpath:, file:, http:, etc.) will be loaded using the specified resource protocol.

The following example demonstrates how to use @Sql at the class level and at the method level within a JUnit-based integration test class.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
@Sql("/test-schema.sql")
public class DatabaseTests {

    @Test
    public void emptySchemaTest {
        // execute code that uses the test schema without any test data
    }

    @Test
    @Sql({"/test-schema.sql", "/test-user-data.sql"})
    public void userTest {
        // execute code that uses the test schema and test data
    }
}

Default script detection

If no SQL scripts are specified, an attempt will be made to detect a default script depending on where @Sql is declared. If a default cannot be detected, an IllegalStateException will be thrown.

Declaring multiple @Sql sets

If multiple sets of SQL scripts need to be configured for a given test class or test method but with different syntax configuration, different error handling rules, or different execution phases per set, it is possible to declare multiple instances of @Sql. With Java 8, @Sql can be used as a repeatable annotation. Otherwise, the @SqlGroup annotation can be used as an explicit container for declaring multiple instances of @Sql.

The following example demonstrates the use of @Sql as a repeatable annotation using Java 8. In this scenario the test-schema.sql script uses a different syntax for single-line comments.

@Test
@Sql(scripts = "/test-schema.sql", config = @SqlConfig(commentPrefix = "`"))
@Sql("/test-user-data.sql")
public void userTest {
    // execute code that uses the test schema and test data
}

The following example is identical to the above except that the @Sql declarations are grouped together within @SqlGroup for compatibility with Java 6 and Java 7.

@Test
@SqlGroup({
    @Sql(scripts = "/test-schema.sql", config = @SqlConfig(commentPrefix = "`")),
    @Sql("/test-user-data.sql")
)}
public void userTest {
    // execute code that uses the test schema and test data
}

Script execution phases

By default, SQL scripts will be executed before the corresponding test method. However, if a particular set of scripts needs to be executed after the test method — for example, to clean up database state — the executionPhase attribute in @Sql can be used as seen in the following example. Note that ISOLATED and AFTER_TEST_METHOD are statically imported from Sql.TransactionMode and Sql.ExecutionPhase respectively.

@Test
@Sql(
    scripts = "create-test-data.sql",
    config = @SqlConfig(transactionMode = ISOLATED)
)
@Sql(
    scripts = "delete-test-data.sql",
    config = @SqlConfig(transactionMode = ISOLATED),
    executionPhase = AFTER_TEST_METHOD
)
public void userTest {
    // execute code that needs the test data to be committed
    // to the database outside of the test's transaction
}

Script configuration with @SqlConfig

Configuration for script parsing and error handling can be configured via the @SqlConfig annotation. When declared as a class-level annotation on an integration test class, @SqlConfig serves as global configuration for all SQL scripts within the test class hierarchy. When declared directly via the config attribute of the @Sql annotation, @SqlConfig serves as local configuration for the SQL scripts declared within the enclosing @Sql annotation. Every attribute in @SqlConfig has an implicit default value which is documented in the javadocs of the corresponding attribute. Due to the rules defined for annotation attributes in the Java Language Specification, it is unfortunately not possible to assign a value of null to an annotation attribute. Thus, in order to support overrides of inherited global configuration, @SqlConfig attributes have an explicit default value of either "" for Strings or DEFAULT for Enums. This approach allows local declarations of @SqlConfig to selectively override individual attributes from global declarations of @SqlConfig by providing a value other than "" or DEFAULT. Global @SqlConfig attributes are inherited whenever local @SqlConfig attributes do not supply an explicit value other than "" or DEFAULT. Explicit local configuration therefore overrides global configuration.

The configuration options provided by @Sql and @SqlConfig are equivalent to those supported by ScriptUtils and ResourceDatabasePopulator but are a superset of those provided by the <jdbc:initialize-database/> XML namespace element. Consult the javadocs of individual attributes in @Sql and @SqlConfig for details.

Transaction management for @Sql

By default, the SqlScriptsTestExecutionListener will infer the desired transaction semantics for scripts configured via @Sql. Specifically, SQL scripts will be executed without a transaction, within an existing Spring-managed transaction — for example, a transaction managed by the TransactionalTestExecutionListener for a test annotated with @Transactional — or within an isolated transaction, depending on the configured value of the transactionMode attribute in @SqlConfig and the presence of a PlatformTransactionManager in the test’s ApplicationContext. As a bare minimum however, a javax.sql.DataSource must be present in the test’s ApplicationContext.

If the algorithms used by SqlScriptsTestExecutionListener to detect a DataSource and PlatformTransactionManager and infer the transaction semantics do not suit your needs, you may specify explicit names via the dataSource and transactionManager attributes of @SqlConfig. Furthermore, the transaction propagation behavior can be controlled via the transactionMode attribute of @SqlConfig — for example, if scripts should be executed in an isolated transaction. Although a thorough discussion of all supported options for transaction management with @Sql is beyond the scope of this reference manual, the javadocs for @SqlConfig and SqlScriptsTestExecutionListener provide detailed information, and the following example demonstrates a typical testing scenario using JUnit and transactional tests with @Sql. Note that there is no need to clean up the database after the usersTest() method is executed since any changes made to the database (either within the the test method or within the /test-data.sql script) will be automatically rolled back by the TransactionalTestExecutionListener (see transaction management for details).

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = TestDatabaseConfig.class)
@Transactional
public class TransactionalSqlScriptsTests {

    protected JdbcTemplate jdbcTemplate;

    @Autowired
    public void setDataSource(DataSource dataSource) {
        this.jdbcTemplate = new JdbcTemplate(dataSource);
    }

    @Test
    @Sql("/test-data.sql")
    public void usersTest() {
        // verify state in test database:
        assertNumUsers(2);
        // execute code that uses the test data...
    }

    protected int countRowsInTable(String tableName) {
        return JdbcTestUtils.countRowsInTable(this.jdbcTemplate, tableName);
    }

    protected void assertNumUsers(int expected) {
        assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"));
    }
}

The Spring TestContext Framework offers full integration with JUnit 4.9+ through a custom runner (supported on JUnit 4.9 through 4.12). By annotating test classes with @RunWith(SpringJUnit4ClassRunner.class), developers can implement standard JUnit-based unit and integration tests and simultaneously reap the benefits of the TestContext framework such as support for loading application contexts, dependency injection of test instances, transactional test method execution, and so on. If you would like to use the Spring TestContext Framework with an alternative runner such as JUnit’s Parameterized or third-party runners such as the MockitoJUnitRunner, you may optionally use Spring’s support for JUnit rules instead.

The following code listing displays the minimal requirements for configuring a test class to run with the custom Spring Runner. @TestExecutionListeners is configured with an empty list in order to disable the default listeners, which otherwise would require an ApplicationContext to be configured through @ContextConfiguration.

@RunWith(SpringJUnit4ClassRunner.class)
@TestExecutionListeners({})
public class SimpleTest {

   @Test
   public void testMethod() {
      // execute test logic...
   }
}

The org.springframework.test.context.junit4.rules package provides the following JUnit rules.

SpringClassRule is a JUnit TestRule that supports class-level features of the Spring TestContext Framework; whereas, SpringMethodRule is a JUnit MethodRule that supports instance-level and method-level features of the Spring TestContext Framework.

In contrast to the SpringJUnit4ClassRunner, Spring’s rule-based JUnit support has the advantage that it is independent of any org.junit.runner.Runner implementation and can therefore be combined with existing alternative runners like JUnit’s Parameterized or third-party runners such as the MockitoJUnitRunner.

In order to support the full functionality of the TestContext framework, a SpringClassRule must be combined with a SpringMethodRule. The following example demonstrates the proper way to declare these rules in an integration test.

// Optionally specify a non-Spring Runner via @RunWith(...)
@ContextConfiguration
public class IntegrationTest {

   @ClassRule
   public static final SpringClassRule SPRING_CLASS_RULE = new SpringClassRule();

   @Rule
   public final SpringMethodRule springMethodRule = new SpringMethodRule();

   @Test
   public void testMethod() {
      // execute test logic...
   }
}

The org.springframework.test.context.junit4 package provides the following support classes for JUnit-based test cases.

AbstractJUnit4SpringContextTests is an abstract base test class that integrates the Spring TestContext Framework with explicit ApplicationContext testing support in a JUnit 4.9+ environment. When you extend AbstractJUnit4SpringContextTests, you can access a protected applicationContext instance variable that can be used to perform explicit bean lookups or to test the state of the context as a whole.

AbstractTransactionalJUnit4SpringContextTests is an abstract transactional extension of AbstractJUnit4SpringContextTests that adds some convenience functionality for JDBC access. This class expects a javax.sql.DataSource bean and a PlatformTransactionManager bean to be defined in the ApplicationContext. When you extend AbstractTransactionalJUnit4SpringContextTests you can access a protected jdbcTemplate instance variable that can be used to execute SQL statements to query the database. Such queries can be used to confirm database state both prior to and after execution of database-related application code, and Spring ensures that such queries run in the scope of the same transaction as the application code. When used in conjunction with an ORM tool, be sure to avoid false positives. As mentioned in Section 14.3, “JDBC Testing Support”, AbstractTransactionalJUnit4SpringContextTests also provides convenience methods which delegate to methods in JdbcTestUtils using the aforementioned jdbcTemplate. Furthermore, AbstractTransactionalJUnit4SpringContextTests provides an executeSqlScript(..) method for executing SQL scripts against the configured DataSource.

	Tip
	These classes are a convenience for extension. If you do not want your test classes to be tied to a Spring-specific class hierarchy, you can configure your own custom test classes by using @RunWith(SpringJUnit4ClassRunner.class) or Spring’s JUnit rules.

The org.springframework.test.context.testng package provides the following support classes for TestNG based test cases.

AbstractTestNGSpringContextTests is an abstract base test class that integrates the Spring TestContext Framework with explicit ApplicationContext testing support in a TestNG environment. When you extend AbstractTestNGSpringContextTests, you can access a protected applicationContext instance variable that can be used to perform explicit bean lookups or to test the state of the context as a whole.

AbstractTransactionalTestNGSpringContextTests is an abstract transactional extension of AbstractTestNGSpringContextTests that adds some convenience functionality for JDBC access. This class expects a javax.sql.DataSource bean and a PlatformTransactionManager bean to be defined in the ApplicationContext. When you extend AbstractTransactionalTestNGSpringContextTests you can access a protected jdbcTemplate instance variable that can be used to execute SQL statements to query the database. Such queries can be used to confirm database state both prior to and after execution of database-related application code, and Spring ensures that such queries run in the scope of the same transaction as the application code. When used in conjunction with an ORM tool, be sure to avoid false positives. As mentioned in Section 14.3, “JDBC Testing Support”, AbstractTransactionalTestNGSpringContextTests also provides convenience methods which delegate to methods in JdbcTestUtils using the aforementioned jdbcTemplate. Furthermore, AbstractTransactionalTestNGSpringContextTests provides an executeSqlScript(..) method for executing SQL scripts against the configured DataSource.

Tip

These classes are a convenience for extension. If you do not want your test classes to be tied to a Spring-specific class hierarchy, you can configure your own custom test classes by using @ContextConfiguration, @TestExecutionListeners, and so on, and by manually instrumenting your test class with a TestContextManager. See the source code of AbstractTestNGSpringContextTests for an example of how to instrument your test class.

The fluent API in the example above requires a few static imports such as MockMvcRequestBuilders.*, MockMvcResultMatchers.*, and MockMvcBuilders.*. An easy way to find these classes is to search for types matching "MockMvc*". If using Eclipse, be sure to add them as "favorite static members" in the Eclipse preferences under Java → Editor → Content Assist → Favorites. That will allow use of content assist after typing the first character of the static method name. Other IDEs (e.g. IntelliJ) may not require any additional configuration. Just check the support for code completion on static members.

There are two main options for creating an instance of MockMvc. The first is to load Spring MVC configuration through the TestContext framework, which loads the Spring configuration and injects a WebApplicationContext into the test to use to create a MockMvc:

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration("my-servlet-context.xml")
public class MyWebTests {

    @Autowired
    private WebApplicationContext wac;

    private MockMvc mockMvc;

    @Before
    public void setup() {
        this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
    }

    // ...

}

The second is to simply create a controller instance manually without loading Spring configuration. Instead basic default configuration, roughly comparable to that of the MVC JavaConfig or the MVC namespace, is automatically created and can be customized to a degree:

public class MyWebTests {

    private MockMvc mockMvc;

    @Before
    public void setup() {
        this.mockMvc = MockMvcBuilders.standaloneSetup(new AccountController()).build();
    }

    // ...

}

Which setup option should you use?

The "webAppContextSetup" loads the actual Spring MVC configuration resulting in a more complete integration test. Since the TestContext framework caches the loaded Spring configuration, it helps to keep tests running fast even as more tests get added. Furthermore, you can inject mock services into controllers through Spring configuration, in order to remain focused on testing the web layer. Here is an example of declaring a mock service with Mockito:

<bean id="accountService" class="org.mockito.Mockito" factory-method="mock">
    <constructor-arg value="org.example.AccountService"/>
</bean>

Then you can inject the mock service into the test in order set up and verify expectations:

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration("test-servlet-context.xml")
public class AccountTests {

    @Autowired
    private WebApplicationContext wac;

    private MockMvc mockMvc;

    @Autowired
    private AccountService accountService;

    // ...

}

The "standaloneSetup" on the other hand is a little closer to a unit test. It tests one controller at a time, the controller can be injected with mock dependencies manually, and it doesn’t involve loading Spring configuration. Such tests are more focused in style and make it easier to see which controller is being tested, whether any specific Spring MVC configuration is required to work, and so on. The "standaloneSetup" is also a very convenient way to write ad-hoc tests to verify some behavior or to debug an issue.

Just like with integration vs unit testing, there is no right or wrong answer. Using the "standaloneSetup" does imply the need for some additional "webAppContextSetup" tests to verify the Spring MVC configuration. Alternatively, you can decide to write all tests with "webAppContextSetup" and always test against actual Spring MVC configuration.

It’s easy to perform requests using any HTTP method:

mockMvc.perform(post("/hotels/{id}", 42).accept(MediaType.APPLICATION_JSON));

You can also perform file upload requests that internally use MockMultipartHttpServletRequest so that there is no actual parsing of a multipart request but rather you have to set it up:

mockMvc.perform(fileUpload("/doc").file("a1", "ABC".getBytes("UTF-8")));

You can specify query parameters in URI template style:

mockMvc.perform(get("/hotels?foo={foo}", "bar"));

Or you can add Servlet request parameters representing either query of form parameters:

mockMvc.perform(get("/hotels").param("foo", "bar"));

If application code relies on Servlet request parameters and doesn’t check the query string explicitly (as is most often the case) then it doesn’t matter which option you use. Keep in mind however that query params provided with the URI template will be decoded while request parameters provided through the param(…​) method are expected to be decoded.

In most cases it’s preferable to leave out the context path and the Servlet path from the request URI. If you must test with the full request URI, be sure to set the contextPath and servletPath accordingly so that request mappings will work:

mockMvc.perform(get("/app/main/hotels/{id}").contextPath("/app").servletPath("/main"))

Looking at the above example, it would be cumbersome to set the contextPath and servletPath with every performed request. Instead you can set up default request properties:

public class MyWebTests {

    private MockMvc mockMvc;

    @Before
    public void setup() {
        mockMvc = standaloneSetup(new AccountController())
            .defaultRequest(get("/")
            .contextPath("/app").servletPath("/main")
            .accept(MediaType.APPLICATION_JSON).build();
    }

The above properties will affect every request performed through the MockMvc instance. If the same property is also specified on a given request, it overrides the default value. That is why the HTTP method and URI in default request don’t matter since they must be specified on every request.

Expectations can be defined by appending one or more .andExpect(..) calls after performing a request:

mockMvc.perform(get("/accounts/1")).andExpect(status().isOk());

MockMvcResultMatchers.* provides a number of expectations some of which are further nested with more detailed expectations.

Expectations fall in two general categories. The first category of assertions verify properties of the response, i.e the response status, headers, and content. Those are the most important results to assert.

The second category of assertions go beyond the response. They allow inspecting Spring MVC specific things such as which controller method processed the request, whether an exception was raised and handled, what the content of the model is, what view was selected, what flash attributes were added, and so on. They also allow inspecting Servlet specific things such as request and session attributes. The following test asserts that binding/validation failed:

mockMvc.perform(post("/persons"))
    .andExpect(status().isOk())
    .andExpect(model().attributeHasErrors("person"));

Many times when writing tests, it’s useful to dump the results of the performed request. This can be done as follows, where print() is a static import from MockMvcResultHandlers:

mockMvc.perform(post("/persons"))
    .andDo(print())
    .andExpect(status().isOk())
    .andExpect(model().attributeHasErrors("person"));

As long as request processing does not cause an unhandled exception, the print() method will print all the available result data to System.out. Spring Framework 4.2 introduces a new log() method and two additional variants of the print() method: one that accepts an OutputStream and one that accepts a Writer. For example, invoking print(System.err) will print the result data to System.err; while invoking print(myWriter) will print the result data to a custom writer. If you would like to have the result data logged instead of printed, simply invoke the log() method which will log the result data as a single DEBUG message under the org.springframework.test.web.servlet.result logging category.

In some cases, you may want to get direct access to the result and verify something that cannot be verified otherwise. This can be done by appending .andReturn() at the end after all expectations:

MvcResult mvcResult = mockMvc.perform(post("/persons")).andExpect(status().isOk()).andReturn();
// ...

When all tests repeat the same expectations you can set up common expectations once when building the MockMvc instance:

standaloneSetup(new SimpleController())
    .alwaysExpect(status().isOk())
    .alwaysExpect(content().contentType("application/json;charset=UTF-8"))
    .build()

Note that the expectation is always applied and cannot be overridden without creating a separate MockMvc instance.

When JSON response content contains hypermedia links created with Spring HATEOAS, the resulting links can be verified:

mockMvc.perform(get("/people").accept(MediaType.APPLICATION_JSON))
    .andExpect(jsonPath("$.links[?(@.rel == ''self'')].href").value("http://localhost:8080/people"));

When XML response content contains hypermedia links created with Spring HATEOAS, the resulting links can be verified:

Map<String, String> ns = Collections.singletonMap("ns", "http://www.w3.org/2005/Atom");
mockMvc.perform(get("/handle").accept(MediaType.APPLICATION_XML))
    .andExpect(xpath("/person/ns:link[@rel=''self'']/@href", ns).string("http://localhost:8080/people"));

When setting up a MockMvc, you can register one or more Filter instances:

mockMvc = standaloneSetup(new PersonController()).addFilters(new CharacterEncodingFilter()).build();

Registered filters will be invoked through MockFilterChain from spring-test and the last filter will delegates to the DispatcherServlet.

As mentioned earlier Spring MVC Test is built on the Servlet API mock objects from the spring-test module and does not rely on a running Servlet container. Therefore there are some important differences compared to full end-to-end integration tests with an actual client and server running.

The easiest way to think about this is starting with a blank MockHttpServletRequest. Whatever you add to it is what the request will be. The things that may catch you out are there is no context path by default, no jsessionid cookie, no forwarding, error, or async dispatches, and therefore no actual JSP rendering. Instead "forwarded" and "redirected" URLs are saved in the MockHttpServletResponse and can be asserted with expectations.

This means if you are using JSPs you can verify the JSP page to which the request was forwarded but there won’t be any HTML rendered. Note however that all other rendering technologies that don’t rely on forwarding such as Thymeleaf, Freemarker, Velocity will render HTML to the response body as expected. The same is true for rendering JSON, XML and others via @ResponseBody methods.

Alternatively you may consider the full end-to-end integration testing support from Spring Boot via @WebIntegrationTest. See the Spring Boot reference.

There are pros and cons for each. The options provided in Spring MVC Test are different stops on the scale from classic unit to full integration tests. To be sure none of the options in Spring MVC Test are classic unit tests but they are a little closer to it. For example you can isolate the service layer with mocks injected into controllers and then you’re testing the web layer only through the DispatcherServlet and with actual Spring configuration, just like you might test the database layer in isolation of the layers above. Or you could be using the standalone setup focusing on one controller at a time and manually providing the configuration required to make it work.

Another important distinction when using Spring MVC Test is that conceptually such tests are on the inside of the server-side so you can check what handler was used, if an exception was handled with a HandlerExceptionResolver, what the content of the model is, what binding errors there were, etc. That means it’s easier to write expectations since the server is not a black box as it is when testing it through an actual HTTP client. This is generally the advantage of classic unit testing that it’s easier to write, reason about, and debug but does not replace the need for full integration tests. At the same time it’s important not to lose sight of the fact the response is the most important thing to check. In short there is room here for multiple styles and strategies of testing even in the same project.

The framework’s own tests include many sample tests intended to demonstrate how to use Spring MVC Test. Browse these examples for further ideas. Also the spring-mvc-showcase has full test coverage based on Spring MVC Test.

The most obvious question that comes to mind is, "Why do I need this?". The answer is best found by exploring a very basic sample application. Assume you have a Spring MVC web application that supports CRUD operations on a Message object. The application also supports paging through all messages. How would you go about testing it?

With Spring MVC Test, we can easily test if we are able to create a Message.

MockHttpServletRequestBuilder createMessage = post("/messages/")
	.param("summary", "Spring Rocks")
	.param("text", "In case you didn't know, Spring Rocks!");

mockMvc.perform(createMessage)
	.andExpect(status().is3xxRedirection())
	.andExpect(redirectedUrl("/messages/123"));

What if we want to test our form view that allows us to create the message? For example, assume our form looks like the following snippet:

<form id="messageForm" action="/messages/" method="post">
  <div class="pull-right"><a href="/messages/">Messages</a></div>

  <label for="summary">Summary</label>
  <input type="text" class="required" id="summary" name="summary" value="" />

  <label for="text">Message</label>
  <textarea id="text" name="text"></textarea>

  <div class="form-actions">
	<input type="submit" value="Create" />
  </div>
</form>

How do we ensure that our form will produce the correct request to create a new message? A naive attempt would look like this:

mockMvc.perform(get("/messages/form"))
	.andExpect(xpath("//input[@name='summary']").exists())
	.andExpect(xpath("//textarea[@name='text']").exists());

This test has some obvious drawbacks. If we update our controller to use the parameter message instead of text, our form test would continue to pass even though the HTML form is out of synch with the controller. To resolve this we can combine our two tests.

String summaryParamName = "summary";
String textParamName = "text";
mockMvc.perform(get("/messages/form"))
		.andExpect(xpath("//input[@name='" + summaryParamName + "']").exists())
		.andExpect(xpath("//textarea[@name='" + textParamName + "']").exists());

MockHttpServletRequestBuilder createMessage = post("/messages/")
		.param(summaryParamName, "Spring Rocks")
		.param(textParamName, "In case you didn't know, Spring Rocks!");

mockMvc.perform(createMessage)
		.andExpect(status().is3xxRedirection())
		.andExpect(redirectedUrl("/messages/123"));

This would reduce the risk of our test incorrectly passing, but there are still some problems.

The overall problem is that testing a web page does not involve a single interaction. Instead, it is a combination of how the user interacts with a web page and how that web page interacts with other resources. For example, the result of a form view is used as the input to a user for creating a message. In addition, our form view may potentially utilize additional resources which impact the behavior of the page, such as JavaScript validation.

This section describes how to integrate MockMvc and HtmlUnit. Use this option if you want to use the raw HtmlUnit libraries.

MockMvc and HtmlUnit Setup

We can easily create an HtmlUnit WebClient that integrates with MockMvc using the MockMvcWebClientBuilder as follows.

@Autowired
WebApplicationContext context;

WebClient webClient;

@Before
public void setup() {
	webClient = MockMvcWebClientBuilder
		.webAppContextSetup(context)
		.build();
}

	Note
	This is a simple example of using MockMvcWebClientBuilder. For advanced usage see the section called “Advanced MockMvcWebClientBuilder”

This will ensure that any URL referencing localhost as the server will be directed to our MockMvc instance without the need for a real HTTP connection. Any other URL will be requested using a network connection as normal. This allows us to easily test the use of CDNs.

MockMvc and HtmlUnit Usage

Now we can use HtmlUnit as we normally would, but without the need to deploy our application to a Servlet container. For example, we can request the view to create a message with the following.

HtmlPage createMsgFormPage = webClient.getPage("http://localhost/messages/form");

	Note
	The default context path is "". Alternatively, we can specify the context path as illustrated in the section called “Advanced MockMvcWebClientBuilder”.

Once we have a reference to the HtmlPage, we can then fill out the form and submit it to create a message.

HtmlForm form = createMsgFormPage.getHtmlElementById("messageForm");
HtmlTextInput summaryInput = createMsgFormPage.getHtmlElementById("summary");
summaryInput.setValueAttribute("Spring Rocks");
HtmlTextArea textInput = createMsgFormPage.getHtmlElementById("text");
textInput.setText("In case you didn't know, Spring Rocks!");
HtmlSubmitInput submit = form.getOneHtmlElementByAttribute("input", "type", "submit");
HtmlPage newMessagePage = submit.click();

Finally, we can verify that a new message was created successfully. The following assertions use the FEST assertion library.

assertThat(newMessagePage.getUrl().toString()).endsWith("/messages/123");
String id = newMessagePage.getHtmlElementById("id").getTextContent();
assertThat(id).isEqualTo("123");
String summary = newMessagePage.getHtmlElementById("summary").getTextContent();
assertThat(summary).isEqualTo("Spring Rocks");
String text = newMessagePage.getHtmlElementById("text").getTextContent();
assertThat(text).isEqualTo("In case you didn't know, Spring Rocks!");

This improves on our MockMvc test in a number of ways. First we no longer have to explicitly verify our form and then create a request that looks like the form. Instead, we request the form, fill it out, and submit it, thereby significantly reducing the overhead.

Another important factor is that HtmlUnit uses the Mozilla Rhino engine to evaluate JavaScript. This means that we can test the behavior of JavaScript within our pages as well!

Refer to the HtmlUnit documentation for additional information about using HtmlUnit.

Advanced MockMvcWebClientBuilder

In the examples so far, we have used MockMvcWebClientBuilder in the simplest way possible, by building a WebClient based on the WebApplicationContext loaded for us by the Spring TestContext Framework. This approach is repeated here.

@Autowired
WebApplicationContext context;

WebClient webClient;

@Before
public void setup() {
	webClient = MockMvcWebClientBuilder
		.webAppContextSetup(context)
		.build();
}

We can also specify additional configuration options.

WebClient webClient;

@Before
public void setup() {
	webClient = MockMvcWebClientBuilder
		// demonstrates applying a MockMvcConfigurer (Spring Security)
		.webAppContextSetup(context, springSecurity())
		// for illustration only - defaults to ""
		.contextPath("")
		// By default MockMvc is used for localhost only;
		// the following will use MockMvc for example.com and example.org as well
		.useMockMvcForHosts("example.com","example.org")
		.build();
}

As an alternative, we can perform the exact same setup by configuring the MockMvc instance separately and supplying it to the MockMvcWebClientBuilder as follows.

MockMvc mockMvc = MockMvcBuilders
		.webAppContextSetup(context)
		.apply(springSecurity())
		.build();

webClient = MockMvcWebClientBuilder
		.mockMvcSetup(mockMvc)
		// for illustration only - defaults to ""
		.contextPath("")
		// By default MockMvc is used for localhost only;
		// the following will use MockMvc for example.com and example.org as well
		.useMockMvcForHosts("example.com","example.org")
		.build();

This is more verbose, but by building the WebClient with a MockMvc instance we have the full power of MockMvc at our fingertips.

	Tip
	For additional information on creating a MockMvc instance refer to the section called “Setup Options”.

In the previous sections, we have seen how to use MockMvc in conjunction with the raw HtmlUnit APIs. In this section, we will leverage additional abstractions within the Selenium WebDriver to make things even easier.

Why WebDriver and MockMvc?

We can already use HtmlUnit and MockMvc, so why would we want to use WebDriver? The Selenium WebDriver provides a very elegant API that allows us to easily organize our code. To better understand, let’s explore an example.

	Note
	Despite being a part of Selenium, WebDriver does not require a Selenium Server to run your tests.

Suppose we need to ensure that a message is created properly. The tests involve finding the HTML form input elements, filling them out, and making various assertions.

This approach results in numerous, separate tests because we want to test error conditions as well. For example, we want to ensure that we get an error if we fill out only part of the form. If we fill out the entire form, the newly created message should be displayed afterwards.

If one of the fields were named "summary", then we might have something like the following repeated in multiple places within our tests.

HtmlTextInput summaryInput = currentPage.getHtmlElementById("summary");
summaryInput.setValueAttribute(summary);

So what happens if we change the id to "smmry"? Doing so would force us to update all of our tests to incorporate this change! Of course, this violates the DRY Principle; so we should ideally extract this code into its own method as follows.

public HtmlPage createMessage(HtmlPage currentPage, String summary, String text) {
	setSummary(currentPage, summary);
	// ...
}

public void setSummary(HtmlPage currentPage, String summary) {
	HtmlTextInput summaryInput = currentPage.getHtmlElementById("summary");
	summaryInput.setValueAttribute(summary);
}

This ensures that we do not have to update all of our tests if we change the UI.

We might even take this a step further and place this logic within an Object that represents the HtmlPage we are currently on.

public class CreateMessagePage {

	final HtmlPage currentPage;

	final HtmlTextInput summaryInput;

	final HtmlSubmitInput submit;

	public CreateMessagePage(HtmlPage currentPage) {
		this.currentPage = currentPage;
		this.summaryInput = currentPage.getHtmlElementById("summary");
		this.submit = currentPage.getHtmlElementById("submit");
	}

	public <T> T createMessage(String summary, String text) throws Exception {
		setSummary(summary);

		HtmlPage result = submit.click();
		boolean error = CreateMessagePage.at(result);

		return (T) (error ? new CreateMessagePage(result) : new ViewMessagePage(result));
	}

	public void setSummary(String summary) throws Exception {
		summaryInput.setValueAttribute(summary);
	}

	public static boolean at(HtmlPage page) {
		return "Create Message".equals(page.getTitleText());
	}
}

Formerly, this pattern is known as the Page Object Pattern. While we can certainly do this with HtmlUnit, WebDriver provides some tools that we will explore in the following sections to make this pattern much easier to implement.

MockMvc and WebDriver Setup

We can easily create a Selenium WebDriver that integrates with MockMvc using the MockMvcHtmlUnitDriverBuilder as follows.

@Autowired
WebApplicationContext context;

WebDriver driver;

@Before
public void setup() {
	driver = MockMvcHtmlUnitDriverBuilder
		.webAppContextSetup(context)
		.build();
}

	Note
	This is a simple example of using MockMvcHtmlUnitDriverBuilder. For more advanced usage, refer to the section called “Advanced MockMvcHtmlUnitDriverBuilder”

This will ensure that any URL referencing localhost as the server will be directed to our MockMvc instance without the need for a real HTTP connection. Any other URL will be requested using a network connection as normal. This allows us to easily test the use of CDNs.

CreateMessagePage page = CreateMessagePage.to(driver);

ViewMessagePage viewMessagePage =
	page.createMessage(ViewMessagePage.class, expectedSummary, expectedText);

public class CreateMessagePage
		extends AbstractPage { 

	
	private WebElement summary;
	private WebElement text;

	
	@FindBy(css = "input[type=submit]")
	private WebElement submit;

	public CreateMessagePage(WebDriver driver) {
		super(driver);
	}

	public <T> T createMessage(Class<T> resultPage, String summary, String details) {
		this.summary.sendKeys(summary);
		this.text.sendKeys(details);
		this.submit.click();
		return PageFactory.initElements(driver, resultPage);
	}

	public static CreateMessagePage to(WebDriver driver) {
		driver.get("http://localhost:9990/mail/messages/form");
		return PageFactory.initElements(driver, CreateMessagePage.class);
	}
}

assertThat(viewMessagePage.getMessage()).isEqualTo(expectedMessage);
assertThat(viewMessagePage.getSuccess()).isEqualTo("Successfully created a new message");

public Message getMessage() throws ParseException {
	Message message = new Message();
	message.setId(getId());
	message.setCreated(getCreated());
	message.setSummary(getSummary());
	message.setText(getText());
	return message;
}

@After
public void destroy() {
	if (driver != null) {
		driver.close();
	}
}

Advanced MockMvcHtmlUnitDriverBuilder

In the examples so far, we have used MockMvcHtmlUnitDriverBuilder in the simplest way possible, by building a WebDriver based on the WebApplicationContext loaded for us by the Spring TestContext Framework. This approach is repeated here.

@Autowired
WebApplicationContext context;

WebDriver driver;

@Before
public void setup() {
	driver = MockMvcHtmlUnitDriverBuilder
		.webAppContextSetup(context)
		.build();
}

We can also specify additional configuration options.

WebDriver driver;

@Before
public void setup() {
	driver = MockMvcHtmlUnitDriverBuilder
		// demonstrates applying a MockMvcConfigurer (Spring Security)
		.webAppContextSetup(context, springSecurity())
		// for illustration only - defaults to ""
		.contextPath("")
		// By default MockMvc is used for localhost only;
		// the following will use MockMvc for example.com and example.org as well
		.useMockMvcForHosts("example.com","example.org")
		.build();
}

As an alternative, we can perform the exact same setup by configuring the MockMvc instance separately and supplying it to the MockMvcHtmlUnitDriverBuilder as follows.

MockMvc mockMvc = MockMvcBuilders
		.webAppContextSetup(context)
		.apply(springSecurity())
		.build();

driver = MockMvcHtmlUnitDriverBuilder
		.mockMvcSetup(mockMvc)
		// for illustration only - defaults to ""
		.contextPath("")
		// By default MockMvc is used for localhost only;
		// the following will use MockMvc for example.com and example.org as well
		.useMockMvcForHosts("example.com","example.org")
		.build();

This is more verbose, but by building the WebDriver with a MockMvc instance we have the full power of MockMvc at our fingertips.

	Tip
	For additional information on creating a MockMvc instance refer to the section called “Setup Options”.

In the previous section, we saw how to use MockMvc with WebDriver. In this section, we will use Geb to make our tests even Groovy-er.

MockMvc and Geb Setup

We can easily initialize a Geb Browser with a Selenium WebDriver that uses MockMvc as follows.

def setup() {
	browser.driver = MockMvcHtmlUnitDriverBuilder
		.webAppContextSetup(context)
		.build()
}

	Note
	This is a simple example of using MockMvcHtmlUnitDriverBuilder. For more advanced usage, refer to the section called “Advanced MockMvcHtmlUnitDriverBuilder”

This will ensure that any URL referencing localhost as the server will be directed to our MockMvc instance without the need for a real HTTP connection. Any other URL will be requested using a network connection as normal. This allows us to easily test the use of CDNs.

MockMvc and Geb Usage

Now we can use Geb as we normally would, but without the need to deploy our application to a Servlet container. For example, we can request the view to create a message with the following:

to CreateMessagePage

We can then fill out the form and submit it to create a message.

when:
form.summary = expectedSummary
form.text = expectedMessage
submit.click(ViewMessagePage)

Any unrecognized method calls or property accesses/references that are not found will be forwarded to the current page object. This removes a lot of the boilerplate code we needed when using WebDriver directly.

As with direct WebDriver usage, this improves on the design of our HtmlUnit test by leveraging the Page Object Pattern. As mentioned previously, we can use the Page Object Pattern with HtmlUnit and WebDriver, but it is even easier with Geb. Let’s take a look at our new Groovy-based CreateMessagePage implementation.

class CreateMessagePage extends Page {
	static url = 'messages/form'
	static at = { assert title == 'Messages : Create'; true }
	static content =  {
		submit { $('input[type=submit]') }
		form { $('form') }
		errors(required:false) { $('label.error, .alert-error')?.text() }
	}
}

The first thing you will notice is that our CreateMessagePage extends Page. We won’t go over the details of Page, but in summary it contains common functionality for all of our pages. The next thing you will notice is that we define a URL in which this page can be found. This allows us to navigate to the page as follows.

to CreateMessagePage

We also have an at closure that determines if we are at the specified page. It should return true if we are on the correct page. This is why we can assert that we are on the correct page as follows.

then:
at CreateMessagePage
errors.contains('This field is required.')

	Note
	We use an assertion in the closure, so that we can determine where things went wrong if we were at the wrong page.

Next we create a content closure that specifies all the areas of interest within the page. We can use a jQuery-ish Navigator API to select the content we are interested in.

Finally, we can verify that a new message was created successfully.

then:
at ViewMessagePage
success == 'Successfully created a new message'
id
date
summary == expectedSummary
message == expectedMessage

For further details on how to get the most out of Geb, consult The Book of Geb user’s manual.

Just like with server-side tests, the fluent API for client-side tests requires a few static imports. Those are easy to find by searching "MockRest*". Eclipse users should add "MockRestRequestMatchers.*" and "MockRestResponseCreators.*" as "favorite static members" in the Eclipse preferences under Java → Editor → Content Assist → Favorites. That allows using content assist after typing the first character of the static method name. Other IDEs (e.g. IntelliJ) may not require any additional configuration. Just check the support for code completion on static members.

Spring MVC Test’s own tests include example tests of client-side REST tests.