This commit improves the Javadoc regarding transactional semantics for
@TransactionalEventListener methods invoked in the AFTER_COMMIT,
AFTER_ROLLBACK, or AFTER_COMPLETION phase. Specifically, the
documentation now points out that interactions with the underlying
transactional resource will not be committed in those phases.
Closes gh-26974
Since Spring Framework 5.2, the LoadTimeWeaver no longer weaves bean
classes annotated with @Component. This is a regression caused by the
changes in 40c62139ae, stemming from the fact that any class annotated
or meta-annotated with @Component is considered to be a candidate
configuration class in 'configuration lite' mode (i.e., a class without
the @Configuration annotation and without any @Bean methods) and
therefore now has its class eagerly loaded. This results in the class
being loaded before the LoadTimeWeaver has a chance to weave it.
This commit fixes this regression by explicitly avoiding eager class
loading for any 'lite' @Configuration or @Component class without @Bean
methods.
Closes gh-26199
Issues gh-25038 and gh-25618 collectively introduced a regression for
thread-scoped and transaction-scoped beans.
For example, given a thread-scoped bean X that depends on another
thread-scoped bean Y, if the names of the beans (when used as map keys)
end up in the same bucket within a ConcurrentHashMap AND an attempt is
made to retrieve bean X from the ApplicationContext prior to retrieving
bean Y, then the use of Map::computeIfAbsent in SimpleThreadScope
results in recursive access to the same internal bucket in the map.
On Java 8, that scenario simply hangs. On Java 9 and higher,
ConcurrentHashMap throws an IllegalStateException pointing out that a
"Recursive update" was attempted.
In light of these findings, we are reverting the changes made to
SimpleThreadScope and SimpleTransactionScope in commits 50a4fdac6e and
148dc95eb1.
Closes gh-25801
PR gh-25038 introduced regressions in SimpleThreadScope and
SimpleTransactionScope in Spring Framework 5.2.7. Specifically, if a
thread-scoped or transaction-scoped bean has a dependency on another
thread-scoped or transaction-scoped bean, respectively, a
ConcurrentModificationException will be thrown on Java 11 or higher.
The reason is that Java 11 introduced a check for concurrent
modification in java.util.HashMap's computeIfAbsent() implementation,
and such a modification can occur when a thread-scoped bean is being
created in order to satisfy a dependency of another thread-scoped bean
that is currently being created.
This commit fixes these regressions by switching from HashMap to
ConcurrentHashMap for the instance maps in SimpleThreadScope and
SimpleTransactionScope.
Closes gh-25618
