Not able insert through jpa outbound gateway - spring-integration

Question

#Bean
public IntegrationFlow reimInvJpaOutbound() {
return IntegrationFlows
.from("reimInvProcessChannel")
.handle(reimJpaHandlers.reimStgInsertJpaHandler())
.log()
.get();
}
#Component
#Transactional
public class ReIMJpaHandlers {
Logger logger = LoggerFactory.getLogger(this.getClass());
#PersistenceContext
protected EntityManager entityManager;
#Autowired
ReIMHistInvHdrStgRepository histRepo;
#Autowired
ReIMInvHdrStgRepository stgRepo;
#Autowired
ReIMErrInvHdrStgRepository errRepo;
String responseQueryString = "select * from RMS16DEV.TSC_IM_DOC_HEAD_TEMP where error_ind != null";
#Bean
public JpaUpdatingOutboundEndpointSpec reimStgInsertJpaHandler() {
System.out.println("Writing to reim stg");
return Jpa
.updatingGateway(entityManager)
.entityClass(TSC_IM_DOC_HEAD_TEMP.class)
;
}
#Bean
public JpaPollingChannelAdapter reimStgResponseJpaInboundAdapter() {
return Jpa
.inboundAdapter(entityManager)
.nativeQuery(responseQueryString)
.maxResults(100)
.get();
}
}
But I am getting below error:
javax.persistence.TransactionRequiredException: No EntityManager with actual transaction available for current thread - cannot reliably process 'merge' call
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:292) ~[spring-orm-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at com.sun.proxy.$Proxy189.merge(Unknown Source) ~[na:na]

Answer 1

Your
#Component
#Transactional
public class ReIMJpaHandlers {
doesn't matter for the
#Bean
public JpaUpdatingOutboundEndpointSpec reimStgInsertJpaHandler() {
The last one is a bean and it lives in its own lifecycle and all its method calls are happened already outside of your #Transactional on the ReIMJpaHandlers.
You need to consider to configure a TX manager exactly for the .handle(reimJpaHandlers.reimStgInsertJpaHandler()):
.handle(reimJpaHandlers.reimStgInsertJpaHandler(), e -> e.transactional())
assuming that you have a bean with the transactionManager name.
The #Transactional on the class is applied for the business methods, but not #Bean methods which are called only once when we create a bean.