FYI: Connect Spring Boot 5.1.16 incompatible with 3.5.6

We updated our Spring Boot from 3.5.4 to 3.5.6. The app seemed to work.

However, the /installed hook does not work, it crashes:

org.springframework.aop.AopInvocationException: Null return value from advice does not match primitive return type for: public abstract long com.atlassian.connect.spring.AtlassianHostMappingRepository.deleteByClientKey(java.lang.String)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:237) ~[spring-aop-6.2.11.jar:6.2.11]
at jdk.proxy4/jdk.proxy4.$Proxy214.deleteByClientKey(Unknown Source) ~[na:na]
at com.atlassian.connect.spring.internal.lifecycle.LifecycleController.installedImpl(LifecycleController.java:157) ~[atlassian-connect-spring-boot-core-5.1.16.jar:na]
at com.atlassian.connect.spring.internal.lifecycle.LifecycleController.lambda$installed$0(LifecycleController.java:107) ~[atlassian-connect-spring-boot-core-5.1.16.jar:na]
at com.atlassian.connect.spring.internal.lifecycle.TransactionExecutor$TransactionCallbackWithTimeout.doInTransaction(TransactionExecutor.java:52) ~[atlassian-connect-spring-boot-core-5.1.16.jar:na]
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140) ~[spring-tx-6.2.11.jar:6.2.11]
at com.atlassian.connect.spring.internal.lifecycle.TransactionExecutor.lambda$executeWithRollbackOption$0(TransactionExecutor.java:43) ~[atlassian-connect-spring-boot-core-5.1.16.jar:na]
at java.base/java.util.Optional.map(Optional.java:260) ~[na:na]

We rolled back to Spring boot 3.5.4 now.
The issue maybe also exists for 3.5.5, we didn’t check.

We also didn’t check Atlassian Connect version 6.0.0 if that one is compatible.

Atlassian Connect Spring Boot version 6.0.0 does not work with Spring Boot version 3.5.6.

It does however work with Spring Boot version 3.5.5.