In my Controller I have injected (#Autowired) this Service, which implements Runnable (I need multi-threading) and I call it like so:
Thread t = new Thread(service);
t.start();
t.join();
Then, in my Service's run() I call this Repository (simple JPARepository), which is injected in Service also with #Autowired:
repository.save(someEntity);
The problem is that it doesn't persist the entity with id=1. The transactional proxy (and Hibernate connection pool) is initialized after the unsuccessful saving of the first entity. After that, it works fine.
Can anyone point me to the right direction with my issue: how to force the Thread to initialize the Hibernate transactional proxy before persisting the first entity?
You should consider to start the thread after Spring context is refreshed. This is safer because all your beans may be in an inconsistent state.
#EventListener(ContextRefreshedEvent.class)
public void handleContextStart() {
// ...
}
Related
I'm working on a mutitenant project it maintains different schema for each tenant, followed Project
As we are dynamically switching the tenants so it looks like some configuration is missed which is closing the session or not keeping the session open to fetch the LAZY loaded objects. Which results in "could not initialize proxy - no session" error.
Please check below link to access the complete project and db schema scripts, please follow the steps given in Readme file.
Project
It will be helpful if someone can point out the issue in the code.
i tried to put service methods in #Transactional annotation but that didn't work.
I'm expecting it to make another call to the LAZY loaded object, This project is simplefied verson of the complex project, actually i have lot more lazy loaded objects.
Issue:-
I'm getting no Session error "could not initialize proxy [com.amran.dynamic.multitenant.tenant.entity.Tenant#1] - no Session"
at line 26 (/dynamicmultitenant/src/main/java/com/amran/dynamic/multitenant/tenant/service/ProductServiceImpl.java)
The issue is that your transaction boundaries are not correct. In TenantDatabaseConfig and MasterDatabaseConfig you've correctly added #EnableTransactionManagement, which will setup transactions when requested.
However - the outermost component that has an (implicit) #Transactional annotation is the ProductRepository (by virtue of it being implemented by the SimpleJpaRepository class - which has the annotation applied to it - https://github.com/spring-projects/spring-data-jpa/blob/864c7c454dac61eb602674c4123d84e63f23d766/spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/support/SimpleJpaRepository.java#L95 )
and so your productRepository.findAll(); call will start a transaction, create a JPA session, run the query, close the session, close the transaction, which means that there is no longer any transaction / session open in which to perform the lazy-loading.
Therefore, your original attempt of
i tried to put service methods in #Transactional annotation but that didn't work.
IS the correct thing to do.
You don't say exactly what you tried to do, and where, but there are a few things that could have gone wrong. Firstly, make sure you're adding a org.springframework.transaction.annotation.Transactional and not a javax.transaction.Transactional annotation.
Secondly (and the more likely problem in this scenario), you'll need to configure the annotation with which transaction manager the transaction should be bound to, otherwise it may use an existing / new transaction created against the master DB connection, not the tenant one.
In this case, I think that:
#Service
#Transactional(transactionManager = "tenantTransactionManager")
public class ProductServiceImpl implements ProductService {
should work for you, and make all the methods of the service be bound to a transaction on the tenant DB connection.
EDIT: Answering a follow-up question:
can you please also suggest a better way to inject my tenantTransactionManager in all my service classes, as I don't want to mention tenantTxnManger in all service classes if there is any better way to do it ?
Yes, sure. You can create a meta-annotation that applies multiple other annotations, so you could create:
/**
* Marks class as being a service operating on a single Tenant
*/
#Target(ElementType.TYPE)
#Retention(RetentionPolicy.RUNTIME)
#Service
#Transactional("tenantTransactionManager")
public #interface TenantService {
}
and then you can simply annotate your service classes with #TenantService instead of #Service:
#TenantService
public class ProductServiceImpl implements ProductService {
Spring is providing one Entity Manager per thread. But I can`t find info if Spring clears Entity Manager after #RestControllers method is finished executing? So for example, if I have a method similar to this
#GetMapping("/{id}")
public ResponseEntity<SomeEntity> someRequest() {
SomeEntity res = someService.doSomeJpaRelatedWork();
return new ResponseEntity<>(res), HttpStatus.OK);
}
Will spring call EntityManager.clear() after the request or will Entity Manager keep entities for further requests on that thread?
Since your method doesn't use an EntityManager nor has it #Transactional annotation it is completely independent of the EntityManager and will on its own not affect any EntityManager.
Also, I doubt anything is Spring will call clear implicitly.
BUT Spring doesn't use one EntityManager per Thread but one per request.
So the next request in your web application will get a fresh EntityManager with a clear 1st level cache. So while the correct answer for the question you asked is "No, clear isn't called", the answer which is probably relevant is "Yes, the EntityManager is clear on each call of your controller method."
We are using declarative spring transaction attribute for database integrity. Some of our code call webservice which do bunch of stuffs in sharepoint. The problem is when webservices take longer time users get deadlock from spring which is holding up backend.
If I make a new thread inside a function which has spring transaction declarative attribute will that be ignored from spring?
[Transaction(TransactionPropagation.Required, ReadOnly = false)]
public void UploadPDFManual(/*parameters*/)
{
//DO some data base related things
if (revisionPDFBytes != null)
{
//my sharepoint call which calls webservice
Task.Factory.StartNew(() => DocumentRepositoryUtil.CreateSharepointDocument(docInfo)); // I draw a new thread from ASPNET worker thread pool.
}
}
Anything other options I should go for?
You don't need doing it in a transaction. Transaction makes a database save an object properly. That's it. All other stuff must be done after the transaction commit. In Java, you can make it with Spring's transaction synchronization or JMS. Take a look at the accepted answer over here.
More useful info specific for .NET (see 17.8).
We have an app that is using hibernate, spring, and DB2 in websphere 7. We have audit triggers and we need to set so the triggers can know the logged in user (we use generic logon to the database). We came up with a new scheme for setting this in a new app so that it can automatically join in new transactions. We overrode the transaction manager and did the work in the doBegin.
These scheme worked great in one app, and seemed to work great in a second app, but now, weeks later, and not consistently (behavior is intermittent and does not happen in local development), we are getting this Pre-bound JDBC Connection found error. Looking online most posts say this is when you use two transaction managers against one data source. That is now what we are doing.
I also read one post wondering if it was because he mixed annotation and AOP based transactions. This app does some of that. I don't really buy that theory, but thought I'd mention it.
Exception:
Caused by:
org.springframework.transaction.IllegalTransactionStateException: Pre-bound JDBC Connection found! HibernateTransactionManager does not support running within DataSourceTransactionManager if told to manage the DataSource itself. It is recommended to use a single HibernateTransactionManager for all transactions on a single DataSource, no matter whether Hibernate or JDBC access.
at java.lang.Throwable.<init>(Throwable.java:67)
at org.springframework.core.NestedRuntimeException.<init>(NestedRuntimeException.java:54)
at org.springframework.transaction.TransactionException.<init>(TransactionException.java:34)
at org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:475)
at gov.usdoj.afms.umc.utils.hibernate.AfmsHibernateTransactionManager.doBegin(AfmsHibernateTransactionManager.java:28)
Code (note that the exception comes from the super.doBegin()):
protected void doBegin(Object arg0, TransactionDefinition arg1) {
super.doBegin(arg0, arg1);
if (!Db2ClientInfo.exists()) {
clearDBProperty();
} else {
setDBProperty(Db2ClientInfo.getClientUserId(), Db2ClientInfo.getClientApplicationId());
}
}
private void setDBProperty(String uId, String appName) {
Session session = getSessionFactory().getCurrentSession();
Properties props = new Properties();
props.setProperty(WSConnection.CLIENT_ID, uId);
props.setProperty(WSConnection.CLIENT_APPLICATION_NAME, appName);
try {
Connection nativeConn = new SimpleNativeJdbcExtractor().getNativeConnection(session.connection());
if (nativeConn instanceof WSConnection) {
WSConnection wconn = (WSConnection) nativeConn;
wconn.setClientInformation(props);
} else {
logger.error("Connection was NOT an instance of WSConnection so client ID and app could not be set");
}
} catch (Exception e) {
throw new RuntimeException("Cannot set DB parameters!", e);
}
}
I just realized I never answered this. It turns out that the exception had nothing whatever to do with our Tx manager. It was the fact that this particular EAR has two apps in it, each pointing to the same data source. Evidently this confuses hibernate. We've plans to separate the apps some day, but creating an identical (except in name) data source and pointing the apps at them separately fixes the issue for now.
Instead of modifying the transaction manager it might be easier (better?) to create a wrapper around your datasource (extending DelegatingDataSource from spring) and override the 2 getConnection methods. For the cleanup you could wrap the connection in a proxy and intercept the close method.
That should be a safer (and easier I guess) way then trying to fiddle with the transaction manager and it works for every technology (JDBC, Hibernate, JPA etc.) as long as you use the wrapped datasource. (The registration could be done with a BeanPostProcessor which detects DataSource instances and simply wraps them in the delegate).
If that is to radical (as it means changing your current applications instead of updating a library). It could be a configuration problem, make sure that you are only loading your configuration (and thus DataSource and TransactionManager) only once, duplicating bean instances might lead to a similair behavior.
For posterity, I just got this problem and the answers here weren't very helpful. We resolved the problem by removing a double import of a core XML file which had the AOP transaction manager definition in it:
<tx:annotation-driven transaction-manager="..."
proxy-target-class="true" />
I'm thinking that it causes there to be 2 transaction managers overlapping the same namespace. To fix it, we moved the imports around so they were being done once.
Hope this helps someone else.
Having spring application (actually grails app) that runs apache-activemq server as spring bean and couple of apache-camel routes. Application use hibernate to work with database. The problem is simple. Activemq+Camel starts up BEFORE grails injects special methods into hibernate domain objects (actually save/update methods etc). So, if activemq already has some data on startup - camel starts processing messages w/o having grails DAO methods injected. This fails with grails.lang.MissingMethodException. Must delay activemq/camel startup before Grails injects special methods into domain objects.
If all these are defined as spring bean, you can use
<bean id="activeMqBean" depends-on="anotherBean" />
This will make sure anotherBean is initialized before activeMqBean
can you move MQ managment into a plugin? It would increase modularity and if you declare in plugin-descriptor
def loadAfter = ['hibernate']
you should have the desired behavior. Works for JBPM plugin
I am not sure in your case but lazy loading may also help e.g.
<bean id="lazybean" class="com.xxx.YourBean" lazy-init="true">
A lazily-initialized bean indicates to the IoC container to create bean instance when it is first requested. This can help you delay the loading of beans you want.
I know this question is pretty old, but I am now facing the same problem in the year 2015 - and this thread does not offer a solution for me.
I came up with a custom processor bean having a CountDownLatch, which I count down after bootstrapping the application. So the messages will be idled until the app has started fully and its working for me.
/**
* bootstrap latch processor
*/
#Log4j
class BootstrapLatchProcessor implements Processor {
private final CountDownLatch latch = new CountDownLatch(1)
#Override
void process(Exchange exchange) throws Exception {
if(latch.count > 0){
log.info "waiting for bootstrapped # ${exchange.fromEndpoint}"
latch.await()
}
exchange.out = exchange.in
}
/**
* mark the application as bootstrapped
*/
public void setBootstrapped(){
latch.countDown()
}
}
Then use it as a bean in your application and call the method setBootstrapped in your Bootstrap.groovy
Then in your RouteBuilder you put the processor between your endpoint and destination for all routes you expect messages coming in before the app has started:
from("activemq:a.in ").processRef('bootstrapProcessor').to("bean:handlerService?method=handle")