ConfigurationPropertiesBindingPostProcessor Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java lines 46–126

public class ConfigurationPropertiesBindingPostProcessor
		implements BeanPostProcessor, PriorityOrdered, ApplicationContextAware, InitializingBean {

	/**
	 * The bean name that this post-processor is registered with.
	 */
	public static final String BEAN_NAME = ConfigurationPropertiesBindingPostProcessor.class.getName();

	@SuppressWarnings("NullAway.Init")
	private ApplicationContext applicationContext;

	@SuppressWarnings("NullAway.Init")
	private BeanDefinitionRegistry registry;

	@SuppressWarnings("NullAway.Init")
	private ConfigurationPropertiesBinder binder;

	@Override
	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
		this.applicationContext = applicationContext;
	}

	@Override
	public void afterPropertiesSet() throws Exception {
		// We can't use constructor injection of the application context because
		// it causes eager factory bean initialization
		this.registry = (BeanDefinitionRegistry) this.applicationContext.getAutowireCapableBeanFactory();
		this.binder = ConfigurationPropertiesBinder.get(this.applicationContext);
	}

	@Override
	public int getOrder() {
		return Ordered.HIGHEST_PRECEDENCE + 1;
	}

	@Override
	public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
		if (!hasBoundValueObject(beanName)) {
			bind(ConfigurationPropertiesBean.get(this.applicationContext, bean, beanName));
		}
		return bean;
	}

	private boolean hasBoundValueObject(String beanName) {
		return BindMethod.VALUE_OBJECT.equals(BindMethodAttribute.get(this.registry, beanName));
	}

	private void bind(@Nullable ConfigurationPropertiesBean bean) {
		if (bean == null) {
			return;
		}
		Assert.state(bean.asBindTarget().getBindMethod() != BindMethod.VALUE_OBJECT,
				"Cannot bind @ConfigurationProperties for bean '" + bean.getName()
						+ "'. Ensure that @ConstructorBinding has not been applied to regular bean");
		try {
			this.binder.bind(bean);
		}
		catch (Exception ex) {
			throw new ConfigurationPropertiesBindException(bean, ex);
		}
	}

	/**
	 * Register a {@link ConfigurationPropertiesBindingPostProcessor} bean if one is not
	 * already registered.
	 * @param registry the bean definition registry
	 * @since 2.2.0
	 */
	public static void register(BeanDefinitionRegistry registry) {
		Assert.notNull(registry, "'registry' must not be null");
		if (!registry.containsBeanDefinition(BEAN_NAME)) {
			BeanDefinition definition = BeanDefinitionBuilder
				.rootBeanDefinition(ConfigurationPropertiesBindingPostProcessor.class)
				.getBeanDefinition();
			definition.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
			registry.registerBeanDefinition(BEAN_NAME, definition);
		}
		ConfigurationPropertiesBinder.register(registry);
	}

}