How to Navigate the Breaking Changes in Spring Cloud Alibaba 2025.1.0.0 for Spring Boot 4

1. bootstrap.yml removed

This is the most disruptive change: the long‑used bootstrap.yml file is completely deprecated in version 2025.1.0.0 and replaced by the spring.config.import mechanism, which loads all configuration in a single context, improving startup speed.

Original bootstrap.yml example:

spring:
  application:
    name: my-service
  cloud:
    nacos:
      config:
        server-addr: 127.0.0.1:8848

After migration, the same settings belong in application.yml with an explicit import:

spring:
  application:
    name: my-service
  config:
    import: nacos:my-service.yml?refreshEnabled=true
  cloud:
    nacos:
      config:
        server-addr: 127.0.0.1:8848

Key point: you must add spring.config.import=nacos:xxx; otherwise the application fails to start with a clear error.

2. Sentinel fully embraces Jackson 3

Spring Boot 4 switches the default JSON library to Jackson 3, and Sentinel has been updated accordingly. The package name changes from com.fasterxml.jackson to the new coordinates, so any code that directly references Jackson internal classes will likely cause compilation errors after upgrade. The new version also improves serialization efficiency for traffic‑governance rules and adds native support for Spring Cloud Gateway 2025 in a reactive WebFlux environment, using Reactor interceptors to enforce rate limiting without blocking event‑loop threads.

3. Nacos 3.1.1 security enhancements

The Nacos client is upgraded from 3.0.3 to 3.1.1. A new sensitive‑field masking feature automatically redacts values of keywords such as password, secret, and token during configuration serialization, preventing accidental leakage in high‑verbosity logs without requiring code changes.

4. Seata adds WebFlux reactive transaction support

Distributed transaction handling now supports the reactive WebFlux stack. Traditional ThreadLocal‑based context propagation does not work when requests hop across threads in a reactive flow. The 2025.1.0.0 release adapts ContextView to automatically pass the transaction XID through reactive streams. Developers only need to add the appropriate annotation to enable AT, TCC, or other transaction modes in reactive applications, and several auto‑configuration bugs have been fixed.

5. RocketMQ module adapts to Spring Boot 4.0

RocketMQ, as a messaging middleware, now fully supports Spring Boot 4.0 via the Spring Cloud Stream RocketMQ Binder. The binder brings more elastic consumption models and, in the Spring Cloud 2025.1 (Oakwood) train, adds fine‑grained control over consumer priority. When RocketMQ is used as the Spring Cloud Bus, configuration‑refresh events propagate about 20 % faster, which is valuable for large‑scale cluster configuration consistency.

Upgrade checklist

JDK version: must be 17 or higher; JDK 21 is recommended for virtual‑thread usage.

Jakarta namespace: replace all javax.* imports with jakarta.* after Spring Boot 3.

Remove the bootstrap starter: delete spring-cloud-starter-bootstrap from pom.xml.

Check serialization code: update any code that depends on old Jackson internal classes.

Connection‑pool compatibility: some users report issues with druid-spring-boot-starter; consider upgrading Druid or switching to HikariCP.

If you have no immediate upgrade plan, you can wait, but for new projects it is advisable to start directly with version 2025.1.0.0.