AbstractApplicationContextRunner

Utility design to run an ApplicationContext and provide AssertJ style assertions. The test is best used as a field of a test class, describing the shared configuration required for the test:

public class MyContextTests {
    private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
            .withPropertyValues("spring.foo=bar")
            .withUserConfiguration(MyConfiguration.class);
}

The initialization above makes sure to register MyConfiguration for all tests and set the spring.foo property to bar unless specified otherwise.

Based on the configuration above, a specific test can simulate what will happen when the context runs, perhaps with overridden property values:

@Test
public someTest() {
    this.contextRunner.withPropertyValues("spring.foo=biz").run((context) -> {
        assertThat(context).containsSingleBean(MyBean.class);
        // other assertions
    });
}

The test above has changed the spring.foo property to biz and is asserting that the context contains a single MyBean bean. The run method takes a ContextConsumer that can apply assertions to the context. Upon completion, the context is automatically closed.

If the application context fails to start the #run(ContextConsumer) method is called with a "failed" application context. Calls to the context will throw an IllegalStateException and assertions that expect a running context will fail. The getFailure() assertion can be used if further checks are required on the cause of the failure:

@Test
public someTest() {
    this.context.withPropertyValues("spring.foo=fails").run((loaded) -> {
        assertThat(loaded).getFailure().hasCauseInstanceOf(BadPropertyException.class);
        // other assertions
    });
}

Parameters

See also

Inheritors