Loading a WebApplicationContext

To instruct the TestContext framework to load a WebApplicationContext instead of a standard ApplicationContext, you can 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 is set to src/main/webapp. This is interpreted as a path relative to the root of your JVM (normally the path to your project). If you are familiar with the directory structure of a web application in a Maven project, you know that src/main/webapp is the default location for the root of your WAR. If you need to override this default, you can provide an alternate path to the @WebAppConfiguration annotation (for example, @WebAppConfiguration("src/test/webapp")). If you wish to reference a base resource path from the classpath instead of the file system, you can use Spring’s classpath: prefix.

Note that Spring’s testing support for WebApplicationContext implementations is on par with its support for standard ApplicationContext implementations. When testing with a WebApplicationContext, you are free to declare XML configuration files, Groovy scripts, or @Configuration classes by using @ContextConfiguration. You are also free to use any other test annotations, such as @ActiveProfiles, @TestExecutionListeners, @Sql, @Rollback, and others.

The remaining examples in this section show some of the various configuration options for loading a WebApplicationContext. The following example shows the TestContext framework’s support for convention over configuration:

Conventions

  • Java

  • Kotlin

@ExtendWith(SpringExtension.class)

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

// detects "WacTests-context.xml" in the same package
// or static nested @Configuration classes
@ContextConfiguration
class WacTests {
	//...
}
@ExtendWith(SpringExtension::class)

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

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

If you annotate a test class with @WebAppConfiguration without specifying a resource base path, the resource path effectively defaults to file:src/main/webapp. Similarly, if you declare @ContextConfiguration without specifying resource locations, component classes, or context initializers, Spring tries to detect the presence of your configuration by using conventions (that is, WacTests-context.xml in the same package as the WacTests class or static nested @Configuration classes).

The following example shows how to explicitly declare a resource base path with @WebAppConfiguration and an XML resource location with @ContextConfiguration:

Default resource semantics

  • Java

  • Kotlin

@ExtendWith(SpringExtension.class)

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

// classpath resource
@ContextConfiguration("/spring/test-servlet-config.xml")
class WacTests {
	//...
}
@ExtendWith(SpringExtension::class)

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

// classpath resource
@ContextConfiguration("/spring/test-servlet-config.xml")
class WacTests {
	//...
}

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.

The following example shows that we can override the default resource semantics for both annotations by specifying a Spring resource prefix:

Explicit resource semantics

  • Java

  • Kotlin

@ExtendWith(SpringExtension.class)

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

// file system resource
@ContextConfiguration("file:src/main/webapp/WEB-INF/servlet-config.xml")
class WacTests {
	//...
}
@ExtendWith(SpringExtension::class)

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

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

Contrast the comments in this example with the previous example.