On behalf of the team and everyone who has contributed, I am pleased to announce a new milestone for the next Spring Framework generation. The fourth milestone continues delivering new features and refinements on top of 7.0.0-M1, 7.0.0-M2 and 7.0.0-M3.
Class-File API usage for Java 24+ apps
Spring Framework reads class bytecode to collect metadata about the application code.
Historically we have used a slim ASM fork for this purpose, through the MetadataReaderFactory and MetadataReader types in the org.springframework.core.type.classreading package.
Although Spring applications typically have no direct exposure to this API, this is especially useful when parsing @Configuration classes or looking for annotations on application code.
Java 24 introduced a new Class-File API with JEP 484 for reading and writing classes as Java bytecode.
Spring Framework 7.0 adopts this feature for Java 24+ applications with a new ClassFileMetadataReader implementation in spring-core.
This should be completely transparent for applications and enabled automatically for Java 24+ runtimes.
New Optional to Object converter
Spring Framework 7.0 will automatically convert an Optional<T> to its contained object thanks to a new OptionalToObjectConverter.
For example, this can be used to transparently unwrap Optional<T> arguments for method invocations in SpEL expressions.
HTTP interface clients
HttpServiceProxyFactory makes it easy to create a proxy for an HTTP interface.
However, it's clear from community feedback that more needs to be done to help with creating tens, maybe hundreds of HTTP service proxies.
With this feature, each service can be associated with a suitably configured HTTP client, and the service can be exposed as a bean to the application.
Our goal here is to provide foundational support for this use case and enable Spring Boot and Spring Cloud users.
We also want to give the Spring Cloud OpenFeign community a migration path to HTTP interface services.
7.0-M4 brings a new registry for HTTP Interface Proxies with an extensible registration DSL. Please refer to the upgrade notes for an example and stay tuned for more information on this feature.
API versioning update
Our new API versioning feature got new updates, with support on the client side and in tests. We'll update the reference documentation and upgrade notes to expand a bit more on that.
And much more!
As usual, you can check the detailed changelog for more details and read the global 7.0 release notes for upgrade concerns.
7.0.0-M4 is now available from https://repo.spring.io and Maven Central.