Доброго времени. Продолжая разбираться с JPA, решил поэксперементировать с transaction-type="JTA". И наткнулся на непонятную проблему: Для начала взял пример из NetBeans (jsfjpa) Посмотрел что там: persistence.xml: | Код |
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" 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_1_0.xsd">
<persistence-unit name="jsf-jpa-war" transaction-type="JTA">
<provider>oracle.toplink.essentials.PersistenceProvider</provider>
<jta-data-source>jdbc/sample</jta-data-source>
<properties>
<property name="toplink.ddl-generation" value="drop-and-create-tables"/>
</properties>
</persistence-unit>
</persistence>
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Код manager-а | Код |
package enterprise.jsf_jpa_war;
import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Resource;
import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;
import javax.persistence.EntityManager;
import javax.persistence.NoResultException;
import javax.persistence.PersistenceContext;
import javax.servlet.http.HttpSession;
import javax.transaction.UserTransaction;
/**
* <p>A simple managed bean to mediate between the user
* and the persistence layer.</p>
* @author rlubke
*/
public class UserManager {
/**
* <p>The key for the session scoped attribute holding the
* appropriate <code>Wuser</code> instance.</p>
*/
public static final String USER_SESSION_KEY = "user";
/**
* <p>The <code>PersistenceContext</code>.</p>
*/
@PersistenceContext
private EntityManager em;
/**
* <p>The transaction resource.</p>
*/
@Resource
private UserTransaction utx;
/**
* <p>User properties.</p>
*/
private String username;
private String password;
private String passwordv;
private String fname;
private String lname;
// -------------------------------------------------------------- Properties
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getPasswordv() {
return passwordv;
}
public void setPasswordv(String passwordv) {
this.passwordv = passwordv;
}
public String getFname() {
return fname;
}
public void setFname(String fname) {
this.fname = fname;
}
public String getLname() {
return lname;
}
public void setLname(String lname) {
this.lname = lname;
}
// ---------------------------------------------------------- Public Methods
/**
* <p>Validates the user. If the user doesn't exist or the password
* is incorrect, the appropriate message is added to the current
* <code>FacesContext</code>. If the user successfully authenticates,
* navigate them to the page referenced by the outcome <code>app-main</code>.
* </p>
*
* @return <code>app-main</code> if the user authenticates, otherwise
* returns <code>null</code>
*/
public String validateUser() {
FacesContext context = FacesContext.getCurrentInstance();
Wuser user = getUser();
if (user != null) {
if (!user.getPassword().equals(password)) {
FacesMessage message = new FacesMessage(FacesMessage.SEVERITY_ERROR,
"Login Failed!",
"The password specified is not correct.");
context.addMessage(null, message);
return null;
}
context.getExternalContext().getSessionMap().put(USER_SESSION_KEY, user);
return "app-main";
} else {
FacesMessage message = new FacesMessage(FacesMessage.SEVERITY_ERROR,
"Login Failed!",
"Username '"
+ username
+
"' does not exist.");
context.addMessage(null, message);
return null;
}
}
/**
* <p>Creates a new <code>Wuser</code>. If the specified user name exists
* or an error occurs when persisting the Wuser instance, enqueue a message
* detailing the problem to the <code>FacesContext</code>. If the
* user is created, move the user back to the login view.</p>
*
* @return <code>login</code> if the user is created, otherwise
* returns <code>null</code>
*/
public String createUser() {
FacesContext context = FacesContext.getCurrentInstance();
Wuser wuser = getUser();
if (wuser == null) {
if (!password.equals(passwordv)) {
FacesMessage message = new FacesMessage("The specified passwords do not match. Please try again");
context.addMessage(null, message);
return null;
}
wuser = new Wuser();
wuser.setFirstname(fname);
wuser.setLastname(lname);
wuser.setPassword(password);
wuser.setUsername(username);
wuser.setSince(new Date());
try {
utx.begin();
em.persist(wuser);
utx.commit();
return "login";
} catch (Exception e) {
FacesMessage message = new FacesMessage(FacesMessage.SEVERITY_ERROR,
"Error creating user!",
"Unexpected error when creating your account. Please contact the system Administrator");
context.addMessage(null, message);
Logger.getAnonymousLogger().log(Level.SEVERE,
"Unable to create new user",
e);
return null;
}
} else {
FacesMessage message = new FacesMessage(FacesMessage.SEVERITY_ERROR,
"Username '"
+ username
+ "' already exists! ",
"Please choose a different username.");
context.addMessage(null, message);
return null;
}
}
/**
* <p>When invoked, it will invalidate the user's session
* and move them to the login view.</p>
*
* @return <code>login</code>
*/
public String logout() {
HttpSession session = (HttpSession)
FacesContext.getCurrentInstance().getExternalContext().getSession(false);
if (session != null) {
session.invalidate();
}
return "login";
}
// --------------------------------------------------------- Private Methods
/**
* <p>This will attempt to lookup a <code>Wuser</code> object
* based on the provided user name.</p>
*
* @return a <code>Wuser</code> object associated with the current
* username, otherwise, if no <code>Wuser</code> can be found,
* returns <code>null</code>
*/
private Wuser getUser() {
try {
Wuser user = (Wuser)
em.createNamedQuery("Wuser.findByUsername").
setParameter("username", username).getSingleResult();
return user;
} catch (NoResultException nre) {
return null;
}
}
}
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Все работает. Стал делать по образу и подобию... persistence.xml такойже код моего класса | Код |
package info.magaz.managers;
import info.magaz.beans.CategoryParents;
import info.magaz.beans.ProductCategory;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Resource;
import javax.persistence.EntityManager;
import javax.persistence.NoResultException;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.transaction.HeuristicMixedException;
import javax.transaction.HeuristicRollbackException;
import javax.transaction.NotSupportedException;
import javax.transaction.RollbackException;
import javax.transaction.SystemException;
import javax.transaction.UserTransaction;
/**
*
* @author vasay
*/
public class ProductCategoryManager {
@PersistenceContext
private EntityManager em;
@Resource
private UserTransaction utx;
@SuppressWarnings("unchecked")
public List getAllProductCategorys()
{
List<ProductCategory> AllCategorys = null;
try {
Query query;
query = em.createNamedQuery("ProductCategory.getAllProductCategory");
AllCategorys = (List<ProductCategory>)query.getResultList();
} catch (NoResultException nre) {
AllCategorys = null;
}
return AllCategorys;
}
}
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Но почему-то у меня em = null. Почему??? Сервер один, база одна... Что-то я не понимаю... --------------------
Придумать идеальную защиту от дурака невозможно, дураки, наудивление, изобретательны. |
Проблема с JPA, transaction-type="JTA" 
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