Prior to this change, by-type lookups using DLBF#getBeanNamesForType
required traversal of all bean definitions within the bean factory
in order to inspect their bean class for assignability to the target
type. These operations are comparatively expensive and when there are a
large number of beans registered within the container coupled with a
large number of by-type lookups at runtime, the performance impact can
be severe. The test introduced here demonstrates such a scenario clearly.
This performance problem is likely to manifest in large Spring-based
applications using non-singleton beans, particularly request-scoped
beans that may be created and wired many thousands of times per second.
This commit introduces a simple ConcurrentHashMap-based caching strategy
for by-type lookups; container-wide assignability checks happen only
once on the first by-type lookup and are afterwards cached by type
with the values in the map being an array of all bean names assignable
to that type. This means that at runtime when creating and autowiring
non-singleton beans, the cost of by-type lookups is reduced to that of
ConcurrentHashMap#get.
Issue: SPR-9448
Backport-Issue: SPR-6870
Backport-Commit: 4c7a1c0a54
Spring Framework
The Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform. A key element of Spring is infrastructural support at the application level: Spring focuses on the "plumbing" of enterprise applications so that teams can focus on application-level business logic, without unnecessary ties to specific deployment environments.
The framework also serves as the foundation for Spring Integration, Spring Batch and the rest of the Spring family of projects. Browse the repositories under the SpringSource organization on GitHub for a full list.
.NET and Python variants are available as well.
Downloading artifacts
Instructions on downloading Spring artifacts via Maven and other build systems are available via the project wiki.
Documentation
See the current Javadoc and Reference docs.
Getting support
Check out the Spring forums and the Spring tag on StackOverflow. Commercial support is available too.
Issue Tracking
Spring's JIRA issue tracker can be found here. Think you've found a bug? Please consider submitting a reproduction project via the spring-framework-issues repository. The readme provides simple step-by-step instructions.
Building from source
Instructions on building Spring from source are available via the project wiki.
Contributing
Pull requests are welcome; you'll be asked to sign our contributor license agreement (CLA). Trivial changes like typo fixes are especially appreciated (just fork and edit!). For larger changes, please search through JIRA for similiar issues, creating a new one if necessary, and discuss your ideas with the Spring team.
Staying in touch
Follow @springframework and its team members on Twitter. In-depth articles can be found at the SpringSource team blog, and releases are announced via our news feed.
License
The Spring Framework is released under version 2.0 of the Apache License.