transactional

I have a drools rule file which uses service classes in the rules. So one rule does something like this: eval(countryService.getCountryById(1) != null) In a validationservice that is annotated with @service and @Transactional(propagation=Propagation.SUPPORTS) the drools file is used in a statelessKnowledgebase and facts are added that should be used in the drool. Once that is done the session.execute(facts) is invoked and the rule engine starts. In order to test the rules I would like to stub the countryService.getCountryById(). No big problem using mockito. Done this for other service that

I have a method as below: ClassA.java @Transactional public void methodA(){ ExecutorService executorService = Executors.newFixedThreadPool(4); executorService.execute(new Runnable() { public void run() { classB.methodB(); } }); } ClassB.java @Transactional public void methodB(){ updateDB(); } Can the methodB work well? Per my understanding, methodB will attach the transaction of methodA, what if methodA exits before methodB? I guess only methodA can be commited by the transaction. But methodB will not commit because the transaction commited before. Can I use @Transactional(propagation =

I have a method annotated with @Transactional. I retrieve an object from my Oracle DB, change a field, and then return from the method. I forgot to save the object, but discovered that the database gets updated anyway. applicationContext <tx:annotation-driven /> <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory" /> </bean> my method @Transactional public void myMethod(long id) { MyObject myObj = dao.getMstAttributeById(id); myObj.setName("new name"); //dao.update(myObj); } my question is why

There are already a few questions about the topic, but no response at all really provides arguments in order to explain why we shouldn't make a Spring MVC controller Transactional . See: Transaction not working correctly - Spring/MyBatis For web MVC Spring app should @Transactional go on controller or service? Making Spring 3 MVC controller method Transactional Spring MVC Controller Transactional So, why? Is there insurmountable technical issues? Is there architectural issues? Is there performance/deadlock/concurrency issues? Are sometimes multiple separate transactions required? If yes, what

Can someone explain what isolation & propagation parameters are for in the @Transactional annotation via real-world example? Basically when and why I should choose to change their default values. Johan Sjöberg Good question, although not a trivial one to answer. Propagation Defines how transactions relate to each other. Common options: Required : Code will always run in a transaction. Creates a new transaction or reuses one if available. Requires_new : Code will always run in a new transaction. Suspends the current transaction if one exists. Isolation Defines the data contract between