I want to build a minimalistic local app that reads/writes HBase via JPA2 without orm.xml and without maven2.
Thereby I use Eclipse with the DataNucleus Plugin whose Enhancer is enabled for the project.
Inspired by
http://matthiaswessendorf.wordpress.com/2010/03/17/apache-hadoop-hbase-plays-nice-with-jpa/
I got the following Entities:
#Entity
#Table(name="account_table")
public class Account
{
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
private String id;
String firstName = null;
String lastName = null;
int level = 0;
#Embedded
Login login = null;
public Account() { }
public Account(String firstName, String lastName, int level, Login login) {
super();
this.firstName = firstName;
this.lastName = lastName;
this.level = level;
this.login = login;
}
and
#Embeddable
public class Login
{
private String login = null;
private String password = null;
public Login() {
// TODO Auto-generated constructor stub
}
public Login(String login, String password) {
super();
this.login = login;
this.password = password;
}
}
The src/META-INF/persistence.xml
<persistence
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
version="1.0">
−
<persistence-unit name="hbase-addressbook"
transaction-type="RESOURCE_LOCAL">
<class>de.syrtec.jpa2hbase.entities.Login</class>
<class>de.syrtec.jpa2hbase.entities.Account</class>
<properties>
<property name="datanucleus.ConnectionURL" value="hbase" />
<property name="datanucleus.ConnectionUserName" value="" />
<property name="datanucleus.ConnectionPassword" value="" />
<property name="datanucleus.autoCreateSchema" value="true" />
<property name="datanucleus.validateTables" value="false" />
<property name="datanucleus.Optimistic" value="false" />
<property name="datanucleus.validateConstraints" value="false" />
</properties>
</persistence-unit>
</persistence>
the DAO:
public class TestDAO {
public static void main(String[] args) {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("hbase-addressbook");
EntityManager em = emf.createEntityManager();
EntityTransaction tx = null;
Account a1 = new Account("myPre", "mySur", 1, new Login("a", "b"));
tx = em.getTransaction();
tx.begin();
em.persist(a1);
tx.commit();
}
}
But when first line of the test DAO is executed...
EntityManagerFactory emf = Persistence.createEntityManagerFactory("hbase-addressbook");
..I get:
11/09/01 06:57:05 INFO DataNucleus.MetaData: Class "de.syrtec.jpa2hbase.entities.Account" has been specified with JPA annotations so using those.
11/09/01 06:57:05 INFO DataNucleus.MetaData: Class "de.syrtec.jpa2hbase.entities.Login" has been specified with JPA annotations so using those.
Exception in thread "main" javax.persistence.PersistenceException: Explicit persistence provider error(s) occurred for "hbase-addressbook" after trying the following discovered implementations: org.datanucleus.api.jpa.PersistenceProviderImpl from provider: org.datanucleus.api.jpa.PersistenceProviderImpl
at javax.persistence.Persistence.createPersistenceException(Persistence.java:242)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:184)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:70)
at de.syrtec.jpa2hbase.start.TestDAO.main(TestDAO.java:15)
Caused by: org.datanucleus.exceptions.NucleusUserException: Errors were encountered when loading the MetaData for the persistence-unit "hbase-addressbook". See the nested exceptions for details
at org.datanucleus.metadata.MetaDataManager.loadPersistenceUnit(MetaDataManager.java:879)
at org.datanucleus.api.jpa.JPAEntityManagerFactory.initialiseNucleusContext(JPAEntityManagerFactory.java:745)
at org.datanucleus.api.jpa.JPAEntityManagerFactory.<init>(JPAEntityManagerFactory.java:422)
at org.datanucleus.api.jpa.PersistenceProviderImpl.createEntityManagerFactory(PersistenceProviderImpl.java:91)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:150)
... 2 more
Caused by: org.datanucleus.exceptions.ClassNotResolvedException: Class "−
de.syrtec.jpa2hbase.entities.Login" was not found in the CLASSPATH. Please check your specification and your CLASSPATH.
at org.datanucleus.JDOClassLoaderResolver.classForName(JDOClassLoaderResolver.java:247)
at org.datanucleus.JDOClassLoaderResolver.classForName(JDOClassLoaderResolver.java:412)
at org.datanucleus.metadata.MetaDataManager.loadPersistenceUnit(MetaDataManager.java:859)
... 6 more
Before I ran the DAO I triggered class enhancing by datanucleus succesfully:
DataNucleus Enhancer (version 3.0.0.release) : Enhancement of classes
DataNucleus Enhancer completed with success for 2 classes. Timings : input=623 ms, enhance=101 ms, total=724 ms. Consult the log for full details
Although I don't understand that enhancing isn't triggered automatically (referring to the logs) despite of having auto-enhancement for the project activated..
Does anybody know why my entities aren't found?
And that minus sign in persistence.xml ?
Related
I'm trying to run a simple web application on which I want run some tests on Jakarta EE 9.1(Full platform). I deployed my application on Glassfish 6.2.5. While I was running some code with jpa implementation this exception is thrown(the persistence provider is EclipseLink 3.0.2):
jakarta.persistence.PersistenceException: Exception [EclipseLink-4002]
(Eclipse Persistence Services - 3.0.2.v202107160933):
org.eclipse.persistence.exceptions.DatabaseException Internal
Exception: java.sql.SQLException: No suitable driver found for
jdbc:mysql://localhost:3306;create=true Error Code: 0
The persistence.xml is:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<persistence xmlns="https://jakarta.ee/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="https://jakarta.ee/xml/ns/persistence https://jakarta.ee/xml/ns/persistence/persistence_3_0.xsd"
version="3.0">
<persistence-unit name="GestoreDB" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<class>testJPA.ValueBeen</class>
<properties>
<property name="jakarta.persistence.schema-generation.action" value="drop-and-create"/>
<property name="jakarta.persistence.schema-generation.scripts.create-target" value="database-and-scripts"/>
<property name="jakarta.persistence.jdbc.driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="jakarta.persistence.jdbc.url" value="jdbc:mysql://localhost:3306;create=true"/>
<property name="jakarta.persistence.jdbc.user" value="root"/>
<property name="jakarta.persistence.jdbc.password" value="myPwd"/>
</properties>
</persistence-unit>
</persistence>
The Entity is(getters and setters omitted):
#Entity
#NamedQuery(name = "ValueBeen.selectTable", query = "select u from ValueBeen u")
public class ValueBeen
{
public ValueBeen(){
}
public ValueBeen(String value)
{
this.value = value;
}
public ValueBeen(int id, String value)
{
this.id = id;
this.value = value;
}
#Id
#GeneratedValue
private int id;
#NotNull
private String value;
...
}
And the WebServlet who perform persistency is:
#WebServlet(name = "helloServlet", value = "/hello-servlet")
public class HelloServlet extends HttpServlet
{
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException
{
ValueBeen valueBeen=new ValueBeen("Hello");
//Manager persistence and manager been
EntityManagerFactory managerPersistence = Persistence.createEntityManagerFactory("GestoreDB");
EntityManager entityManager = managerPersistence.createEntityManager();
//Do persistence
EntityTransaction transaction = entityManager.getTransaction();
transaction.begin();
entityManager.persist(valueBeen);
transaction.commit();
//close managers
entityManager.close();
managerPersistence.close();
}
}
I put the jdbc connector jar (Mysql connector 8.0.28) in .\glassfish-6.2.5\glassfish\domains\domain1\lib
As you deploy your app to glassfish container then "transaction-type" in persistence.xml i guess should be "JTA", and property "jakarta.persistence.jdbc.url" is invalid because you do not indicate any database / schema name after ":3306". Glassfish documentation provides instructions and examples how to setup global jdbc connections and those limited to only application scope.
I am trying to build a simple REST service, using JAX-RS, that will perform the standard CRUD operations on a database table. I am able to successfully query for records, but I cannot insert new ones. I do not get any errors and when I step through the code in debug mode everything looks good. I am using a transactional CDI bean running in a Glassfish 4.1 container.
It feels like it's just never committing the transaction. I'm pretty new to Java EE, but my understanding is that since the bean is transactional the container should handle the commit for me. Anyone know why it is not?
#Path("/recipes")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public class RecipeResource {
#Inject
RecipesService recipesService;
#GET
public List<Recipe> getRecipes() {
return recipesService.getAllRecipes();
}
#POST
public void addRecipse(Recipe recipe) {
recipesService.addRecipe(recipe);
}
}
public class RecipesService {
#PersistenceContext(unitName="PANTRYDB", type=PersistenceContextType.TRANSACTION)
EntityManager em;
public RecipesService () {
}
public List<Recipe> getAllRecipes () {
List<Recipe> recipes = null;
try {
TypedQuery<Recipe> typedQuery = em.createQuery("select r from Recipe r", Recipe.class);
recipes = typedQuery.getResultList();
} catch (Exception e) {
System.out.println(e);
}
return recipes;
}
#Transactional
//This is the method that seems to not commit it's transaction
//The Recipe object is populated correctly, and the persist() doesn't
//throw any errors
public void addRecipe(Recipe recipe) {
try {
em.persist(recipe);
} catch (Exception e) {
System.out.println(e);
}
}
}
#Entity
#Table(name="RECIPES", schema="COOKBOOK")
public class Recipe {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
private int id;
#Column
private String name;
#Column(name="CREATED_DATE")
private Calendar createdDate;
#Column(name="LAST_MADE_DATE")
private Calendar lastMadeDate;
#Column
private String description;
#Column
private String notes;
public int getId() {
return id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Calendar getCreatedDate() {
return createdDate;
}
public void setCreatedDate(Calendar createdDate) {
this.createdDate = createdDate;
}
public Calendar getLastMadeDate() {
return lastMadeDate;
}
public void setLastMadeDate(Calendar lastMadeDate) {
this.lastMadeDate = lastMadeDate;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getNotes() {
return notes;
}
public void setNotes(String notes) {
this.notes = notes;
}
#Override
public String toString() {
return name;
}
}
Persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="PANTRYDB" transaction-type="JTA">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<class>com.domain.Recipe</class>
<properties>
<property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.EmbeddedDriver" />
<property name="javax.persistence.jdbc.url" value="jdbc:derby:/Users/development/eclipse/ws_playground/databases/pantry_db/PANTRYDB" />
<property name="hibernate.dialect" value="org.hibernate.dialect.DerbyDialect"/>
<property name="javax.persistence.jdbc.user" value=""/>
<property name="javax.persistence.jdbc.password" value=""/>
</properties>
</persistence-unit>
</persistence>
I tried your application on a weblogic 12.2.1 and it successfully inserted in database and i do not have any problem with transaction.
Here is my code.
RecipeResource class (I modified the #Path to call it via web browser and also instanciated the Recipe manually):
#Path("/recipes")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public class RecipeResource {
#Inject
RecipesService recipesService;
#GET
#Path("get")
public List<Recipe> getRecipes() {
return recipesService.getAllRecipes();
}
#GET
#Path("add")
public String addRecipse() {
Recipe recipe = new Recipe();
recipe.setDescription("desc");
recipesService.addRecipe(recipe);
return "OK";
}
}
The Recipe class is same as yours except that i commented the schema :
#Entity
#Table(name="RECIPES") //, schema="COOKBOOK")
public class Recipe {
}
My persistence.xml (I'm using in-memory database):
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns /persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0">
<persistence-unit name="PANTRYDB" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/__default</jta-data-source>
<class>org.jvi.webservice.transactional.db.Recipe</class>
<properties>
<!--<property name="eclipselink.ddl-generation" value="create-tables"/>-->
<property name="eclipselink.ddl-generation" value="drop-and-create-tables"/>
<property name="eclipselink.logging.level" value="FINE"/>
<property name="eclipselink.logging.level.sql" value="FINE"/>
<property name="eclipselink.logging.parameters" value="true"/>
<property name="eclipselink.logging.logger" value="DefaultLogger"/>
<property name="eclipselink.cache.shared.default" value="false"/>
</properties>
</persistence-unit>
So your problem might come from the Application Server.
Did you try to deploy your webapp on another server?
When you are using JTA transaction management, responsibility for creating and managing database connections is provided by application server, not your application.
Basically, you have to configure your data source in your GlassFish server instance, not directly in persistence.xml via properties:
Configure connection pool and datasource JNDI name in your GlassFish server instance
Link data source configuration in your persistence.xml via <jta-data-source> element
Please check this answer for further details:
https://stackoverflow.com/a/9137741/1980178
Are you sure you are not mixing two frameworks. RecipeResource has a #Path annotation which is from the JavaEE framework, and the #Transactional annotation is from the Spring framework, I think you should replace it with #TransactionAttribute which is the equivalent JavaEE anotation.
Have a look here for details between transaction in Spring an JavaEE
My ejb code:
#Stateless
public class EmployeeBean {
#PersistenceContext(unitName="Eclipselink_JPA")
private EntityManager entitymanager;
public void createEmployee(){
Employee employee = new Employee( );
employee.setEid( 1201 );
employee.setEname( "Gopal" );
employee.setSalary( 40000 );
employee.setDeg( "Technical Manager" );
entitymanager.persist( employee );
entitymanager.getTransaction( ).commit( );
entitymanager.close( );
}
}
Basically, nullpointer exception happens at the line where entitymanager.persist is called, which should not happen right?
My persistence.xml file
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="Eclipselink_JPA" transaction-type="RESOURCE_LOCAL">
<class>com.jpa.beans.Employee</class>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:hsqldb:file:E:\HQLDB_AJ"/>
<property name="javax.persistence.jdbc.user" value="sa"/>
<property name="javax.persistence.jdbc.password" value="password"/>
<property name="javax.persistence.jdbc.driver" value="org.hsqldb.jdbc.JDBCDriver"/>
<property name="eclipselink.logging.level" value="FINE"/>
<property name="eclipselink.ddl-generation" value="create-tables"/>
</properties>
</persistence-unit>
</persistence>
I have eclipselink.jar and other eclipselink jpa jars in my class path.
Here is my entity beans:
#Entity
#Table
public class Employee {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int eid;
private String ename;
private double salary;
private String deg;
public Employee(int eid, String ename, double salary, String deg) {
super( );
this.eid = eid;
this.ename = ename;
this.salary = salary;
this.deg = deg;
}
public Employee( ) {
super();
}
public int getEid( ) {
return eid;
}
public void setEid(int eid) {
this.eid = eid;
}
public String getEname( ) {
return ename;
}
public void setEname(String ename) {
this.ename = ename;
}
public double getSalary( ) {
return salary;
}
public void setSalary(double salary) {
this.salary = salary;
}
public String getDeg( ) {
return deg;
}
public void setDeg(String deg) {
this.deg = deg;
}
#Override
public String toString() {
return "Employee [eid=" + eid + ", ename=" + ename + ", salary=" + salary + ", deg=" + deg + "]";
}
}
Whats seems to be the problem? can anyone help? ive been figuring this out of a day now.
Problem solved: i shouldn't be using resource local because i was running it in an app server. thanks for the help anyway. well appreciated
When you set transaction-type="RESOURCE_LOCAL" in persistence.xml config file, it means that YOU (=your application's code) will take care of creating EntityManager and also will handle transactions yourself. In such case what you can demand to be injected by your underlying container is EntityManagerFactory and you can do it by using #PersistenceUnit annotation. On such object you simply call createEntityManager() that gives you EntityManager.
If you want to use EntityManager supplied by the container you must specify transaction-type="JTA". Then you annotate EntityManager exactly as in your code, and do not care of creating, committing or rolling back a transaction. It will be done by the container that will use JTA transaction and decide when to create, commit or rollback it.
Those two ways are commonly known as respectively Application Managed EntityManager and Container Managed EntityManager
You can find more details on how to work with each of two ways of handling transactions here or here
You dont have <provider> in your persistence.xml.. Try adding it.
Ex:
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
or <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider> or
<provider>org.hibernate.ejb.HibernatePersistence</provider>
depending on your container.
HTH
I'm trying to create EntityManager in my webapp, but it's failing with:
No suitable driver found for jdbc:postgresql:://localhost/database
However the same persistance unit and the same code for creating EntityManager works when I run it as JavaSE console application (from main() ).
Googling gave me several common problems causing that error:
JDBC url is wrong
Shouldn't be since it works from main
JDBC Driver is not in the class path
I can create a Class object using Class.forName("org.postgresql.Driver"); for the driver so I think it is in the classpath.
Other things I tried:
I thought maybe the driver jar from glassfish/lib and the webapp/WEB-INF/lib are conflicting somehow so I tried with both of them together and separately, no luck.
Recreated a small new webapp hoping the problem will go away, it didn't :-)
Inject #PersistanceUnit - also didn't work, don't know is it the same issue or I didn't use it properly as I'm still learning about injection and EJBs
Thanks
Full error:
javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.2.v20111125-r10461): org.eclipse.persistence.exceptions.DatabaseException Internal Exception: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost/database Error Code: 0
Here is the code:
ManagedBean in webapp:
#ManagedBean
public class TestBean {
private String entry;
private String driver;
public String getFromDatabase(){
EntityManagerFactory emf = Persistence.createEntityManagerFactory("Unit1");
EntityManager em = emf.createEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
EntityOne one = new EntityOne();
one.id = 1;
one.entry = "Bla bla";
em.persist(one);
tx.commit();
em.close();
return "done";
}
public String createDriver(){
try {
Class d = Class.forName("org.postgresql.Driver");
driver = d.getName();
} catch (ClassNotFoundException e) {
driver = "Class not found";
return "";
}
return "";
}
public String getDriver() {
return driver;
}
public void setDriver(String driver) {
this.driver = driver;
}
public String getEntry() {
return entry;
}
public void setEntry(String entry) {
this.entry = entry;
}
}
Same code working in main:
public class Standalone {
public static void main(String[] args) {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("Unit1");
EntityManager em = emf.createEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
EntityOne one = new EntityOne();
one.id = 1;
one.entry = "Bla bla";
em.persist(one);
tx.commit();
em.close();
}
}
persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<persistence-unit name="Unit1" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<class>com.test.EntityOne</class>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost/database"/>
<property name="javax.persistence.jdbc.user" value="darko"/>
<property name="javax.persistence.jdbc.password" value="sifra"/>
<property name="eclipselink.target-database" value="PostgreSQL"/>
</properties>
</persistence-unit>
Place the posgres jdbc driver into the lib of glassfish. Its something like this.
[glassfish_home]/glassfish/domains/YOUR_DOMAIN/lib/
Also, restart the server after this.
I'm new to JPA, and i got this infamous error "no persistence provider for entitymanager named". I search far and wide on google, and tried every single solution available, to no extent i'm afraid.
Stack Trace
javax.persistence.PersistenceException: No Persistence provider for EntityManager named suplink
at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
at com.supinfo.suplink.util.PersistenceManager.getEntityManagerFactory(PersistenceManager.java:13)
Persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<persistence-unit name="suplink" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver" />
<property name="javax.persistence.jdbc.user" value="root" />
<property name="javax.persistence.jdbc.password" value="" />
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/SupLink" />
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect" />
</properties>
<class>com.supinfo.suplink.entity.User</class>
</persistence-unit>
PersistenceManager
public class PersistenceManager {
private static EntityManagerFactory emf;
private PersistenceManager() { }
public static EntityManagerFactory getEntityManagerFactory() {
if(emf == null) {
emf = Persistence.createEntityManagerFactory("suplink");
}
return emf;
}
public static void closeEntityManagerFactory() {
if(emf != null && emf.isOpen()) emf.close();
}
}
Thanks for your help :)
try to remove the transaction-type="RESOURCE_LOCAL"
works on my machine without this code
Good luck for your graded exercise, try code underneath ;)
public class PersistenceManager {
private static final EntityManagerFactory emf;
private static final ThreadLocal<EntityManager> threadLocal;
private static final Logger logger;
static {
emf = Persistence.createEntityManagerFactory("SupLink");
threadLocal = new ThreadLocal<EntityManager>();
logger = Logger.getLogger("SupLink");
logger.setLevel(Level.ALL);
}
public static EntityManager getEntityManager() {
EntityManager manager = threadLocal.get();
if (manager == null || !manager.isOpen()) {
manager = emf.createEntityManager();
threadLocal.set(manager);
}
return manager;
}
public static void closeEntityManager() {
EntityManager em = threadLocal.get();
threadLocal.set(null);
if (em != null)
em.close();
}
public static void beginTransaction() {
getEntityManager().getTransaction().begin();
}
public static void commit() {
getEntityManager().getTransaction().commit();
}
public static void rollback() {
getEntityManager().getTransaction().rollback();
}
public static Query createQuery(String query) {
return getEntityManager().createQuery(query);
}
public static void log(String info, Level level, Throwable ex) {
logger.log(level, info, ex);
}
}