Improve inline documentation for PostProcessorRegistrationDelegate

This commit introduces warnings in invokeBeanFactoryPostProcessors()
and registerBeanPostProcessors() to deter people from submitting PRs
that result in breaking changes.

Closes gh-26401
This commit is contained in:
Sam Brannen
2021-01-22 13:34:29 +01:00
parent aa7584d252
commit 9d8910d869

View File

@@ -1,5 +1,5 @@
/*
* Copyright 2002-2020 the original author or authors.
* Copyright 2002-2021 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -59,6 +59,19 @@ final class PostProcessorRegistrationDelegate {
public static void invokeBeanFactoryPostProcessors(
ConfigurableListableBeanFactory beanFactory, List<BeanFactoryPostProcessor> beanFactoryPostProcessors) {
// WARNING: Although it may appear that the body of this method can be easily
// refactored to avoid the use of multiple loops and multiple lists, the use
// of multiple lists and multiple passes over the names of processors is
// intentional. We must ensure that we honor the contracts for PriorityOrdered
// and Ordered processors. Specifically, we must NOT cause processors to be
// instantiated (via getBean() invocations) or registered in the ApplicationContext
// in the wrong order.
//
// Before submitting a pull request (PR) to change this method, please review the
// list of all declined PRs involving changes to PostProcessorRegistrationDelegate
// to ensure that your proposal does not result in a breaking change:
// https://github.com/spring-projects/spring-framework/issues?q=PostProcessorRegistrationDelegate+is%3Aclosed+label%3A%22status%3A+declined%22
// Invoke BeanDefinitionRegistryPostProcessors first, if any.
Set<String> processedBeans = new HashSet<>();
@@ -192,6 +205,19 @@ final class PostProcessorRegistrationDelegate {
public static void registerBeanPostProcessors(
ConfigurableListableBeanFactory beanFactory, AbstractApplicationContext applicationContext) {
// WARNING: Although it may appear that the body of this method can be easily
// refactored to avoid the use of multiple loops and multiple lists, the use
// of multiple lists and multiple passes over the names of processors is
// intentional. We must ensure that we honor the contracts for PriorityOrdered
// and Ordered processors. Specifically, we must NOT cause processors to be
// instantiated (via getBean() invocations) or registered in the ApplicationContext
// in the wrong order.
//
// Before submitting a pull request (PR) to change this method, please review the
// list of all declined PRs involving changes to PostProcessorRegistrationDelegate
// to ensure that your proposal does not result in a breaking change:
// https://github.com/spring-projects/spring-framework/issues?q=PostProcessorRegistrationDelegate+is%3Aclosed+label%3A%22status%3A+declined%22
String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanPostProcessor.class, true, false);
// Register BeanPostProcessorChecker that logs an info message when