DefaultApplicationContextFactory Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/DefaultApplicationContextFactory.java lines 38–90

class DefaultApplicationContextFactory implements ApplicationContextFactory {

	// Method reference is not detected with correct nullability
	@SuppressWarnings("NullAway")
	@Override
	public @Nullable Class<? extends ConfigurableEnvironment> getEnvironmentType(
			@Nullable WebApplicationType webApplicationType) {
		return getFromSpringFactories(webApplicationType, ApplicationContextFactory::getEnvironmentType, null);
	}

	// Method reference is not detected with correct nullability
	@SuppressWarnings("NullAway")
	@Override
	public @Nullable ConfigurableEnvironment createEnvironment(@Nullable WebApplicationType webApplicationType) {
		return getFromSpringFactories(webApplicationType, ApplicationContextFactory::createEnvironment, null);
	}

	// Method reference is not detected with correct nullability
	@SuppressWarnings("NullAway")
	@Override
	public ConfigurableApplicationContext create(@Nullable WebApplicationType webApplicationType) {
		try {
			return getFromSpringFactories(webApplicationType, ApplicationContextFactory::create,
					this::createDefaultApplicationContext);
		}
		catch (Exception ex) {
			throw new IllegalStateException("Unable create a default ApplicationContext instance, "
					+ "you may need a custom ApplicationContextFactory", ex);
		}
	}

	private ConfigurableApplicationContext createDefaultApplicationContext() {
		if (!AotDetector.useGeneratedArtifacts()) {
			return new AnnotationConfigApplicationContext();
		}
		return new GenericApplicationContext();
	}

	@Contract("_, _, !null -> !null")
	private <T> @Nullable T getFromSpringFactories(@Nullable WebApplicationType webApplicationType,
			BiFunction<ApplicationContextFactory, @Nullable WebApplicationType, @Nullable T> action,
			@Nullable Supplier<T> defaultResult) {
		for (ApplicationContextFactory candidate : SpringFactoriesLoader.loadFactories(ApplicationContextFactory.class,
				getClass().getClassLoader())) {
			T result = action.apply(candidate, webApplicationType);
			if (result != null) {
				return result;
			}
		}
		return (defaultResult != null) ? defaultResult.get() : null;
	}

}