Develop Reference

Configure Spring transactions or EJB CMT instead

I tried to configure Spring Boot with Hibernate:
import javax.persistence.EntityManager;
import javax.persistence.EntityTransaction;
import org.datalis.plugin.database.dao.TerminalsService;
import org.datalis.plugin.database.models.TerminalsModel;
import org.hibernate.Session;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
#Service
#Qualifier("terminalsService")
public class TerminalsDaoHibernate implements TerminalsService {
#Autowired
private EntityManager entityManager;
#Override
#Transactional
public TerminalsModel getTerminalToken(String terminalToken) throws Exception {
TerminalsModel terminal = null;
Session session = entityManager.unwrap(Session.class);
try {
entityManager.getTransaction().begin();
terminal = (TerminalsModel) session.get(TerminalsModel.class, terminalToken);
session.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
session.getTransaction().rollback();
throw new Exception("Error");
}
return terminal;
}
}
But I get this error:
14:47:34,323 ERROR [stderr] (default task-1) java.lang.IllegalStateException: Not allowed to create transaction on shared EntityManager - use Spring transactions or EJB CMT instead
14:47:34,323 ERROR [stderr] (default task-1) at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:255)
What is the proper way to configure #Transactional properly?
Do I need to use Transaction is a different way?

You are using #Transactional and still are trying to manually start a transaction. Either do manual transaction management (i.e remove the #Transactional) or embrace #Transactional by removing the manual transaction management code.
#Override
#Transactional
public TerminalsModel getTerminalToken(String terminalToken) throws Exception {
TerminalsModel terminal = null;
Session session = entityManager.unwrap(Session.class);
return (TerminalsModel) session.get(TerminalsModel.class, terminalToken);
}
However I don't see why you would want to use plain Hibernate over JPA here. The same result can be achieved by using JPA.
#Override
#Transactional
public TerminalsModel getTerminalToken(String terminalToken) throws Exception {
return entityManager.find(TerminalsModel.class, terminalToken);
}
Generally there is no need to use the plain Hibernate API over JPA with the current state of the JPA API.

EntityManager em.getTransaction().begin() locks thread

My question is, if the method "begin()" is capable of lock a thread further than the "timeout" config in the persistence.xml.
Here is a snippet:
#Inject EntityManager em;
#Inject ContextControl ctxCtrl;
String fileType;
String fileName;
String hash;
BufferedReader reader = null;
public void run(File f, String fileType, String hash) throws ProcessorException, IOException{
this.fileType = fileType;
this.hash= hash;
this.fileName = f.getName();
try {
ctxCtrl.startContext(RequestScoped.class);
em.getTransaction().begin();
reader = openReader(f);
//rest of the code...
em.getTransaction().commit();
}catch (Exception e) {
logger.error(e.getMessage(), e);
try{ //for database breakdown purpose
em.getTransaction().rollback();
}catch(Exception e2){
logger.error(e2.getMessage(), e2);
throw new ProcessorException();
}
throw new ProcessorException();
}finally{
reader.close();
ctxCtrl.stopContext(RequestScoped.class);
}
"run" method is executed inside a loop. This method is executed serially, there is no possible concurrency.
Now, the thing is that the thread stops randomly at line "em.getTransaction().begin();", with no exception. And since this is a critical area, all the application is stopped and the lock is never released.
The only thing I can think of is the "begin()" method getting stuck somehow, but not in an exception way, but rather in a lock way (since no exception is caught).
I wasn't able to recreate the issue, I can only say that the issue has nothing to do with the file. Also, this is happening in production, so I can't debug the application other than check some logs
thanks in advance
EDIT
I use Deltaspike to provide the CDI. Entitymanager it's injected anytime it's needed. It's created like this:
CLASS ENTITYMANAGER FACTORY PRODUCER
import java.io.FileInputStream;
import java.util.Properties;
import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.context.RequestScoped;
import javax.enterprise.inject.Disposes;
import javax.enterprise.inject.Produces;
import javax.inject.Inject;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import org.slf4j.Logger;
#ApplicationScoped
public class EntityManagerFactoryProducer {
#Inject Logger logger;
#Produces
#ApplicationScoped
public EntityManagerFactory create() {
Properties props = new Properties();
try {
props.load(new FileInputStream("cfg/connection.properties"));
} catch (Exception e) {
logger.error(e.getMessage(), e);
}
return Persistence.createEntityManagerFactory("scgach",props);
}
public void destroy(#Disposes EntityManagerFactory factory) {
factory.close();
}
}
CLASS ENTITYMANAGER PRODUCER
import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.context.RequestScoped;
import javax.enterprise.inject.Disposes;
import javax.enterprise.inject.Produces;
import javax.inject.Inject;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
#ApplicationScoped
public class EntityManagerProducer {
#Inject EntityManagerFactory emf;
#Produces #RequestScoped
public EntityManager create() {
return emf.createEntityManager();
}
public void destroy(#Disposes EntityManager em) {
if(em.isOpen())
em.close();
}
}

NameAlreadyBoundException using JNDI

I created a session bean with this code:
package ejb2;
import javax.annotation.Resource;
import javax.ejb.SessionContext;
import javax.ejb.Stateless;
#Stateless(name = "TestEJB", mappedName = "EJB2-Project1-TestEJB")
public class TestEJBBean implements TestEJB, TestEJBLocal {
#Resource
SessionContext sessionContext;
public TestEJBBean() {
}
public String getHello(String who_welcome) {
return "Hello " + who_welcome;
}
}
As you can see, it's almost a default code (except getHello method). Besides this bean I have a client:
package ejb2;
import java.util.Hashtable;
import javax.naming.CommunicationException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class TestEJBClient {
public static void main(String[] args) {
try {
final Context context = getInitialContext();
TestEJB testEJB = (TestEJB) context.lookup("EJB2-Project1-TestEJB#ejb2.TestEJB");
System.out.println(testEJB.getHello("Student"));
} catch (CommunicationException ex) {
System.out.println(ex.getClass().getName());
System.out.println(ex.getRootCause().getLocalizedMessage());
System.out.println("\n*** A CommunicationException was raised. This typically\n*** occurs when the target WebLogic server is not running.\n");
} catch (Exception ex) {
ex.printStackTrace();
}
}
private static Context getInitialContext() throws NamingException {
Hashtable env = new Hashtable();
// WebLogic Server 10.x/12.x connection details
env.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory");
env.put(Context.PROVIDER_URL, "t3://localhost:7101");
return new InitialContext(env);
}
}
First time it worked like a charm. But then I created another bean:
package ejb2;
import javax.annotation.Resource;
import javax.ejb.Stateless;
import javax.ejb.SessionContext;
import javax.naming.Context;
import javax.naming.InitialContext;
#Stateless(name = "ClientEJB", mappedName = "EJB2-Project1-ClientEJB")
public class ClientEJBBean implements ClientEJB, ClientEJBLocal {
#Resource
SessionContext sessionContext;
TestEJB testEJB;
public ClientEJBBean() {
try {
final Context context = new InitialContext();
testEJB = (TestEJB) context.lookup("EJB2-Project1-TestEJB#ejb2.TestEJB");
} catch (Exception ex) {
ex.printStackTrace();
}
}
public String getHelloFromBean(String who) {
return testEJB.getHello(who);
}
}
And now beans aren't working. I get an error like this:
weblogic.application.ModuleException: Unable to bind Business Interface to the JNDI name: EJB2Project1WebApp_warClientEJB_Home, throw exception javax.naming.NameAlreadyBoundException: [EJB:011224]Unable to bind the interface ejb2.ClientEJB to ClientEJB. Another EJB has already bound an interface to that name.; remaining name 'EJB2-Project1-ClientEJB#ejb2'. NestedException Message is :[EJB:011224]Unable to bind the interface ejb2.ClientEJB to ClientEJB. Another EJB has already bound an interface to that name.
What's the problem with these codes?

As far as i can see you try to deploy two stateless EJBs with the same JNDI name
Try to undeploy the current application , check the JNDI tree from Admin Console
and make sure the tree does not have the JNDI name you see as duplicate.

How to run Application Client on the GlassFish Server 4 from command line

I just started to learn EJB and I wrote a simple bean and client application. Below is a code:
Interface:
package ejb;
import javax.ejb.Remote;
#Remote
public interface MySessionRemote {
String getResult();
}
Bean:
import javax.ejb.EJB;
import javax.ejb.Stateless;
#Stateless
public class MySession implements MySessionRemote {
// #EJB
//private static MySessionRemote mySession1;
#Override
public String getResult() {
return "Bean";
}
}
Client application:
package entappclient;
import javax.naming.*;
import ejb.MySessionRemote;
import java.util.Properties;
import javax.ejb.EJB;
public class Main {
// #EJB private static MySessionRemote mySession;
public static void main(String[] args) {
// TODO code application logic here
new Main().Save();
}
public Context getContext() throws javax.naming.NamingException {
Properties props = new Properties();
props.setProperty("java.naming.factory.initial",
"com.sun.enterprise.naming.SerialInitContextFactory");
props.setProperty("java.naming.factory.url.pkgs",
"com.sun.enterprise.naming");
props.setProperty("java.naming.factory.state",
"com.sun.corba.ee.impl.presentation.rmi.JNDIStateFactoryImpl");
props.setProperty("org.omg.CORBA.ORBInitialHost", "localhost");
return new InitialContext(props);
}
public void Save () {
//System.out.println(mySession1.getResult());
try {
Context jndiContext = getContext();
System.out.println("0");
MySessionRemote ref = ySessionRemote)jndiContext.lookup("java:global/EntAppEJB- ejb/MySession!ejb.MySessionRemote");
System.out.println("1");
System.out.println(ref.getResult());
} catch (Exception e ) {
System.out.println("Save"+e);
}
}
}
When I run it under NetBeans 8 everything works fine. The result is:
0
1
Bean
But when I try to run this from command line using : appclient - client path/EntAppClient.jar, it does not work. The result is:
0
Savejavax.naming.NamingException: Lookup failed for 'java:global/EntAppEJB-ejb/M
ySession!ejb.MySessionRemote' in SerialContext[myEnv={java.naming.factory.initia
l=com.sun.enterprise.naming.SerialInitContextFactory, org.omg.CORBA.ORBInitialHo
st=localhost, java.naming.factory.state=com.sun.corba.ee.impl.presentation.rmi.J
NDIStateFactoryImpl, java.naming.factory.url.pkgs=com.sun.enterprise.naming} [Ro
ot exception is javax.naming.NamingException: ejb ref resolution error for remot
e business interfaceejb.MySessionRemote [Root exception is java.lang.ClassNotFou
ndException: ejb.MySessionRemote]]
Can anybody help me to find out why I can run this under NetBeans but it does not work from command line.
Best regards
Marcin

Stateless is not working in AS 7

I'm getting this:
[org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/PontoComentario].[jsp]] (http--0.0.0.0-8080-2) Servlet.service() for servlet jsp threw exception: org.hibernate.LazyInitializationException: could not initialize proxy - no Session
at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:149) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:195) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:185) [hibernate-core-4.0.1.Final.jar:4.0.1.Final
After acessing the jsp. My EMFactory is like this:
import javax.ejb.Stateless;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.persistence.EntityManager;
import javax.transaction.UserTransaction;
#Stateless
public class EMFactory {
public static EntityManager getEntityManager() {
try {
Context ctx = new InitialContext();
return (EntityManager) ctx.lookup("java:comp/env/PontoComentario/EntityManager");
} catch (Exception e) {
return null;
}
}
public static UserTransaction getUserTransaction() {
try {
Context ctx = new InitialContext();
return (UserTransaction) ctx.lookup("java:comp/UserTransaction");
} catch (Exception e) {
return null;
}
}
}
I'm not sure why i'm getting that, i was using AS 5 and it was working nice. If you need any other piece of code just ask.
This is a sad part of scriptlets that was use in the jsp:
<%
UsuarioDao dao = new UsuarioDao();
List<Usuario> lista;
if (usuarioLogado.getAdministrador()) {
lista = dao.getListOrder("codigo");
} else {
lista = dao.getListCond("obj.administrador = true order by obj.codigo");
... and so on.

Why don't you simply inject a reference to the EntityManager with an annotation:
#PersistenceContext
EntityManager em;
And are you really accessing your SLSB from a JSP? Not from a servlet controller?