Spring transaction management using JDBC and Hibernate 4 together - java

We are using JPA (Hibernate 4) with Spring 4 managing the JTA transactions. Since there are parts of the application using JDBC to access the database as well, we need to make sure JDBC and JPA join the same transaction to see what the other changed before commit.
You can find a test case for these questions on GitHub https://github.com/abenneke/sandbox/tree/master/spring-hibernate4-transaction
To have JDBC and JPA join the same transaction and see the changes the other made, we had to use the TransactionAwareDataSourceProxy for Hibernate/JPA as well. With all the other transaction configuration around, this however seems to be redundant. Did we miss something? Or is this the suggested way to achieve the requirement?
Thank you!

I think you can achieve the same outcome with much less configuration hassle if you stock to Hibernate and your JTA DataSource while you use the Session.doWork for your JDBC code.
You don't need TransactionAwareDataSourceProxy, since you want to use Transaction services anyway and not call DAO classes outside of a transactional service.
You need to add:
<bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect"/>
and make sure you supply it to testEntityManager
<bean id="testEntityManager" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="testDataSource">
...
<property name="jpaDialect" ref="jpaDialect"/>
</bean>
Update
In one application we developed recently we too mixed JPA and JDBCTemplate and it worked nicely because Bitronix PoolingDataSource was instructed to always return the same connection for the current running thread.
For this you have to set the following Bitronix property:
shareTransactionConnections=true

Related

Is it possible to combine a container managed and application managed entitymanager in a bean?

I am using container managed transactions in my JavaEE application, but, as I have understood it, container managed entitymanagers lacks support for batch inserts. And now I have a case where I will insert a lot of data into the DB. Is it possible, in some way, to combine a container managed entitymanager with an application managed entitymanager in a bean?
If so, I could make a method in my bean that commits the data after I have called entitymanager.persist(myEntity); several times, making it a batch insert.
But to get that working, I now have to set #TransactionManagement(TransactionManagementType.BEAN) for the whole class/bean, making the whole bean application managed. But I want my other methods to be container managed, just one method (the method making batch inserts) to be application managed.
Is that possible or are there any other approaches for cases like this?
JDBC batching is a cross-cutting concern and you can get it working for all entity manager configurations.
First you need to set the following Hibernate properties:
<property name="hibernate.order_updates" value="true"/>
<property name="hibernate.order_inserts" value="true"/>
<property name="hibernate.jdbc.batch_versioned_data" value="true"/>
<property name="hibernate.jdbc.fetch_size" value="20"/>
<property name="hibernate.jdbc.batch_size" value="50"/>
Also make sure you use SEQUENCE or TABLE identifier generators since IDENTITY will disable JDBC batching

Spring Transaction management - How to know the API is executed in one transaction or not?

How to know if my particular flow or API is getting executed in one transaction or not ?
I am using the JPATransactionManager
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"
p:entityManagerFactory-ref="entityManagerFactory" />
I am using #Transactional annotation at API to declare the transactional boundaries.
I am trying hard to find out clear transaction boundaries in my application and know when particular transaction is getting started, when particular transaction is ended.. I also tried logs for JPATranscationManager at Trace level but didn't help much.

Using JOTM transaction manager Doesn't works on Tomcat

Facing a strange problem here, below is the configuration i am using:
1. Apache Tomcat 6.0.26
2. mySql
3. Spring framework+ Hibernate
We have used JOTM for transaction management
<bean id="jotm"
class="org.springframework.transaction.jta.JotmFactoryBean" />
<bean id="transactionManager"
class="org.springframework.transaction.jta.JtaTransactionManager">
< property name="userTransaction" ref="jotm" />
</bean>
The problem is that i have one service which creates and entity on my local DB and then calls a web service on failiure of which the created entity in local DB should be rolled back. On failure of the web service call i am throwing RunTimeException which should ideally rollback the transaction as per mentioned in the spring configuration file. However this is not happening. Instead of JOTM if i am using Hibernate transaction manager it is rolling back the transaction. Can someone please throw some light on if i am missing out on anything while implementing through JOTM.
Appreciate the help in advance,
Vaibhav

Problem managing session with multiple data sources

I am working on a project where we each service refers four separate data-source. Until now, we have been using ProxyFactoryBean to refer to the Dao target and the Transaction Intereceptor - something like this..
<bean id="readOnlyUserProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
<property name="target" ref="readOnlyDao"/>
<property name="interceptorNames">
<list>
<value>readOnlyTransactionInterceptor</value>
</list>
</property>
</bean>
There are 3 other similar proxies for the different DAOs . All these refer to different transaction interceptors which in turn connect to different transaction managers. In short, each service connects to 4 dao proxies each of which refer a separate transaction interceptor, each of which in turn refer to a separate transaction manager connecting to 4 different data sources. All work fine till now with lazy="false".
Now, In order to optimize the performance, we wish to enable 'Lazy loading' and carry the hibernate session to the handler layer. We think that the best way for this would be through the 'TransactionProxyFactoryBean' as we do not want to use the OpenSessionInView approach .
We have tried some approaches but are stuck because we connect to 4 separate data sources through each service and in now way can we connect the four separate transaction managers to the 'TransactionProxyFactoryBean'. Therefore, we are not able to find a way to manage the transactions from different data sources in the handler/service layer.
I have just started on this work and do not have much experience in Spring transaction management. Kindly guide me on any possible approach I could take.
Managing transactions across multiple datasources is the job of the application server. The appserver will expose those transactions via the JTA API, and Spring can bridge from the JPA API to the Spring API using JtaTransactionManager.
As for how to configure the app server itself, that depends on what app server it is, you should do some research into that documention. It can be quite a complex operation, especially if the data sources are spread across different database servers (in which case you get into needing an XA Transaction Monitor, and it all gets very complicated).

JPA Multiple Transaction Managers

I have one applicationContext.xml file, and it has two org.springframework.orm.jpa.JpaTransactionManager (each with its own persistence unit, different databases) configured in a Spring middleware custom application.
I want to use annotation based transactions (#Transactional), to not mess around with TransactionStatus commit, save, and rollback.
A coworker mentioned that something gets confused doing this when there are multiple transaction managers, even though the context file is set configured correctly (the references go to the correct persistence unit.
Anyone ever see an issue?
In your config, would you have two transaction managers?
Would you have txManager1 and txManager2?
That's what I have with JPA, two different Spring beans that are transaction managers.
I guess you have 2 choices
If your use-cases never require updates to both databases within the same transaction, then you can use two JpaTransactionManagers, but I'm not sure you will be able to use the #Transactional approach? In this case, you would need to fallback on the older mechanism of using a simple TransactionProxyFactoryBean to define transaction boundaries, eg:
<bean id="firstRealService" class="com.acme.FirstServiceImpl"/>
<bean id="firstService"
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
<property name="transactionManager" ref="firstJpaTm"/>
<property name="target" ref="firstRealService"/>
<property name="transactionAttributes">
<props>
<prop key="insert*">PROPAGATION_REQUIRED</prop>
<prop key="update*">PROPAGATION_REQUIRED</prop>
<prop key="*">PROPAGATION_REQUIRED,readOnly</prop>
</props>
</property>
</bean>
<!-- similar for your second service -->
If you are require a transaction spanning both databases, then you will need to use a JTA transaction manager. The API states:
This transaction manager is appropriate for applications that use a single JPA EntityManagerFactory for transactional data access. JTA (usually through JtaTransactionManager) is necessary for accessing multiple transactional resources within the same transaction. Note that you need to configure your JPA provider accordingly in order to make it participate in JTA transactions.
What this means is that you will need to provide a JTA transaction manager. In our application, we use config similar to the following:
<tx:annotation-driven transaction-manager="txManager"/>
<bean id="txManager"
class="org.springframework.transaction.jta.JtaTransactionManager">
<property name="transactionManagerName" value="appserver/jndi/path" />
</bean>
If you are deploying within an appserver, then the spring JtaTransactionManager needs to do a lookup to the real XA-compliant JTA transaction manager provided by the appserver. However, you can also use a standalone JTA transaction manager (but I haven't tried this myself yet)
As for configuring the Jpa persistence provider, I'm not that familiar. What JPA persistence provider are you using?
The code above is based on our approach, where we were using native Hibernate as opposed to Hibernate's JPA implementation. In this case, we were able to get rid of the two HibernateTransactionManager beans, and simply ensure that both SessionFactories were injected with the same JTA TM, and then use the tx:annotation-driven element.
Hope this helps
The only situation in which you can have two Spring transaction managers is if you never have both transactions open at one time. This is not intrinsically to do with distributed transactions - the same restrictions apply even if you want the two datasources to have completely separate (but potentially overlapping in time) transaction lifecyles.
Internally Spring's transaction managers all use Spring's TransactionSynchronizationManager which keeps a bunch of critical state in static ThreadLocal variables, so transaction managers are guaranteed to stomp all over each other's state.

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