Navigating the End of Life for Spring Framework 5.3 and 6: What You Need to Know

As the Spring Framework approaches its end-of-life (EOL) for versions 5.3 and 6.0, organizations relying on these versions must brace themselves for significant changes. The official support for these versions will cease, meaning no more updates, patches, or security fixes—leaving your applications vulnerable to new security threats.

If you are concerned about migrating in time, consider using our Never-Ending Support for Spring Framework, which extends the support of your Spring until you are ready to migrate. 

Breaking Changes in Spring Framework 5.3 and 6.0

Spring Framework 5.3 and 6.0 introduced several breaking changes that developers need to be aware of when considering migration or continued use without official support:

1. Java Version Requirements:
   • Spring Framework 6.0: With this version, the minimum Java version was increased to 17. This change forces a significant shift for projects that were still on older versions, particularly in long-term enterprise environments.
2. Jakarta EE 9 Requirements
   • While Spring Framework 5.3 requires Java EE 7 at minimum, Spring Framework 6.0 came with an upgrade to Jakarta EE version 9 at minimum. Even though Spring makes the upgrade to 6.0 straightforward, there is still a great deal of work for some applications that should be handled with care.
3. Deprecation and Removal of Features:
   • Several features and APIs that were deprecated in earlier versions were removed or reworked in Spring Framework 6.0, leading to potential compatibility issues for legacy applications. This includes changes to core annotations, AOP (Aspect-Oriented Programming), and data access frameworks.
   • The removal of long-deprecated classes and methods in Spring Framework 5.3 and 6.0 requires careful attention during migration to ensure no broken dependencies.
4. Module Changes and Refactoring:
   • Spring Framework 6.0 refactored several modules to better align with modern application development practices. While this refactoring is beneficial in the long run, it requires developers to update their codebases, affecting dependency management and module imports.
   • Users with heavily customized or extended Spring components might find that certain internal APIs have changed, necessitating code rewrites.
5. Security Configurations:
   • Significant updates to security configurations, especially in Spring Security, have been made across these versions. These include changes to default security settings and introducing new security practices that require reconfiguring existing setups.

Migration Strategies for Spring Framework Users

Migrating from Spring Framework 5.3 or 6.0 to newer versions or alternative frameworks can be complex, especially for large-scale enterprise applications. However, if your migration will take an extended amount of time, you can stay secure on deprecated versions of Spring with NES for Spring Framework. 

Here’s a step-by-step guide to help you through this transition:

1. Assessment of Current Codebase:
   • Start by auditing your current application to identify dependencies, deprecated features, and areas where breaking changes may impact functionality.
   • Evaluate the compatibility of your existing Java version with newer Spring versions or other frameworks.
2. Incremental Upgrades:
   • If you're still on a version older than Spring 5.3, consider the latest Spring 5.3.x before moving to newer versions (see Spring Framework 5.x upgrade guide). This incremental upgrade approach helps mitigate the risk by allowing you to address changes in smaller, more manageable steps. The goal is to get your application to Spring Framework 6 generation. Even better, if your application uses Spring Boot, this upgrade guide will be beneficial to get it up to date with Spring Boot 3 (which uses Spring Framework 6). Once you are on Spring Boot 3.0 and Spring Framework 6.0, use the following release notes and upgrade guides to get on the latest versionssome text
     1. Spring Framework 6 Upgrades
     2. Spring Boot 3.x Release Notes (3.0, 3.1, 3.2, 3.3)
   • Keep in mind that most Spring powered applications also depend on a number of other Spring Projects, such as Spring Security, Spring WebMVC, etc. As you upgrade, make sure to check compatibility matrices across these dependencies and migrate as necessary. 
3. Review Release Notes:
   • For the versions you are upgrading, understand key changes to APIs, new features, CVE patches, and transitive dependency upgrades (.e.g. Tomcat, Hibernate, etc.). This information is incredibly helpful during the functional and performance testing phases of the upgrade. 
4. Refactoring and Testing:
   • Refactor your codebase to replace deprecated features and accommodate breaking changes. This may involve rewriting certain components, updating dependency management, and modifying configurations.
   • Implement comprehensive testing to ensure that the migrated application functions and performs correctly and securely, especially in areas impacted by security updates. Integration-level tests can be helpful here since they should not only assert the application’s business logic and outcomes but also show how the business code uses the Spring Framework. A solid integration testing suite can help identify issues with the Spring Framework upgrade early in the upgrade process. 
5. Leverage Professional Support
   • Utilize services like our Never-Ending Support for Spring Framework to ensure security and compliance during the transition. Our secure drop-in replacement seamlessly provides security and compliance fixes.

Conclusion

The end-of-life of Spring Framework 5.3 and 6.0 is more than just a milestone—it's a critical juncture for organizations relying on these frameworks. With breaking changes, the need for migration, and the ongoing demand for support in order to be compliant and secure, it’s essential to approach this transition strategically. Our Never-Ending Support for Spring Framework offers a reliable solution to keep your applications running smoothly and securely, giving you the flexibility to put your business first.