https://www.baeldung.com/spring-data-neo4j-intro explains how to configure Spring with Neo4J and use repositories to get data.
https://neo4j.com/docs/ogm-manual/current/tutorial/#tutorial-session shows how to create a CRUD service using the Session object.
As written in the Session Javadoc, Session object is not thread safe.
Most of our DAO objects are singletons used by many threads. So the Session class member should be replaced by a SessionFactory which will create a new Session each time we need it.
The Service calling the DAO is annotated with @Transactional to have transaction support on all his methods.
Running this code causes a org.neo4j.ogm.exception.core.TransactionManagerException: Transaction is not current for this thread
The code of Neo4jTransactionManager shows that a new Session is opened when starting a transaction.
And it is stored in the TransactionSynchronizationManager, a « thread local holder » that is cleared at the end of the transaction.
The created Session can easily be retrieved through the TransactionSynchronizationManager.
The following DAO work fine if we are in a Spring-managed transactional context
Java Knight 