Uses Spring Framework 6 and Spring Security 6 under the hood
Needs at least Java 17 (we can use records now for POJOs)
All the components marked @Deprecated in Spring Boot 2.x are removed from the code
Jump from Java EE to Jakarta EE9: javax.* packages are now jakarta.*.
URL pattern matching changed. URLs terminated with slash (localhost:8080/foo/) no longer redirect to non-terminating with slash (“normal”) ones (localhost:8080/foo). link
Additions and Improvements
Spring Native: Maven Build Plugin supports AoT image generation with GraalVM out-of-the-box, without the need for any third-party dependency
ProblemDetail response object for better error reporting
Improvements to Micrometer (Observability API): wraps around endpoint responses to observe and gather stats. We can now know the an endpoint’s hit count, request processing times, etc.
@HttpExchange (works just like OpenFeign but without the need for any third-party dependency)