/* JpaUtil.java
{{IS_NOTE
Purpose:
Description:
History:
Mon Dec 17 2007, Created by jeffliu
}}IS_NOTE
Copyright (C) 2006 Potix Corporation. All Rights Reserved.
{{IS_RIGHT
}}IS_RIGHT
*/
package org.zkoss.zkplus.jpa;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import org.hibernate.HibernateException;
import org.zkoss.util.logging.Log;
import org.zkoss.zk.ui.Desktop;
import org.zkoss.zk.ui.Execution;
import org.zkoss.zk.ui.Executions;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.WebApp;
/**
* This class is used to create and hold open EntityManagerFactory objects
* within a Java EE environment.
*
* @author Jeff
* @since 3.0.2
*/
public class JpaUtil {
private static final Log log = Log.lookup(JpaUtil.class);
public static final String CONFIG = "JpaUtil.PersistenceUnitName";
public static final String JPA_EMF_MAP = "org.zkoss.zkplus.jpa.EmfMap";
public static final String JPA_EM_MAP = "org.zkoss.zkplus.jpa.EmMap";
/*
* Get the EntityManagerFactories Map from WebApp scope
*/
private static Map getEmfMap() {
final Map appattrs = getWebApp().getAttributes();
Map map = (Map) appattrs.get(JPA_EMF_MAP);
if (map == null) {
map = new HashMap();
appattrs.put(JPA_EMF_MAP, map);
}
return map;
}
/*
* Get the EntityManagers Map from Execution scope
*/
private static Map getEmMap() {
Execution current = Executions.getCurrent();
Map map = (Map) current.getAttribute(JPA_EM_MAP);
if (map == null) {
map = new HashMap();
Executions.getCurrent().setAttribute(JPA_EM_MAP, map);
}
return map;
}
/**
* Create or return the default EntityManagerFactory as defined in zk.xml.
*
* <p>
* In WEB-INF/zk.xml, add following lines:
*
* <pre><code>
*<preference>
* <name>JPA.PersistenceUnitName</name>
* <value>PERSISTENCE_UNIT_NAME</value>
*</preference>
* </code></pre>
*
* </p>
*
* @return EntityManagerFactory
*/
public static EntityManagerFactory getEntityManagerFactory() {
return initEntityManagerFactory(null, null);
}
/**
* Create or return the EntityManagerFactory for the specified persistence
* unit name. </br>*Notice:If the EntityManagerFactory with specified
* persistence unit is not created yet, a new one will be created.
*
* @param puName Persistence unit name
* @return EntityManagerFactory
*/
public static EntityManagerFactory getEntityManagerFactory(String puName) {
return initEntityManagerFactory(puName, null);
}
/**
* Create the EntityManagerFactory for the specified persistence unit and
* defined properties. </br>*Notice: It always creates a new
* EntityManagerFactory unless properties is null.
*
* @param puName Persistence unit name
* @param properties Defined priorities
* @return EntityManagerFactory
*/
public static EntityManagerFactory getEntityManagerFactory(String puName,
Map properties) {
return initEntityManagerFactory(puName, properties);
}
/**
* Returns an EntityManager of the default EntityManagerFactory as defined in zk.xml in an Execution scope.
* <p>
* In WEB-INF/zk.xml, add following lines:
*
* <pre><code>
*<preference>
* <name>JPA.PersistenceUnitName</name>
* <value>PERSISTENCE_UNIT_NAME</value>
*</preference>
* </code></pre>
*
* </p>
* @return EntityManager
*/
public static EntityManager getEntityManager() {
return initEntityManger(null, null);
}
/**
* Returns or create an EntityManager for the specified persistence unit name. </br>*Notice:If
* the EntityManagerFactory with specified presistence unit is not created
* before, a new one will be created automatically.
* <p>The EntityManager get by this method is guaranteed to be the same within one Execution for the
* specified persistence unit name.</p>
*
* @param puName -
* Persistence unit name
* @return EntityManager
*/
public static EntityManager getEntityManager(String puName) {
return initEntityManger(puName, null);
}
/**
* Closes the EntityManager of the default EntityManagerFactory as
* defined in zk.xml in an Execution scope. It is equals to
* closeEntityManager(null).
* <p>
* In WEB-INF/zk.xml, add following lines:
*
* <pre><code>
*<preference>
* <name>JPA.PersistenceUnitName</name>
* <value>PERSISTENCE_UNIT_NAME</value>
*</preference>
* </code></pre>
* @since 3.0.7
*/
public static void closeEntityManager() {
closeEntityManager(null);
}
/**
* Closes the EntityManager of the EntityManagerFactory of the specified puName;
* @since 3.0.7
*/
public static void closeEntityManager(String puName) {
EntityManager em = (EntityManager) getEmMap().remove(getPersistenceUnitName(puName));
if (em != null && em.isOpen()) em.close();
}
/**
* Returns an EntityManager for the specified persistence unit name and
* defined properties. </br>*Notice: It always creates a new EntityManagerFactory
* and thus a new EntityManager unless properties is null.
*
* @param puName -
* Persistence unit name
* @param properties -
* Defined priorities
* @return EntityManager
*/
public static EntityManager getEntiyManager(String puName, Map properties) {
return initEntityManger(puName, properties);
}
/*
* If EntityManagerFactory with persistence name puName is not found in Map,
* created a new one and return; or return a new created EntityManagerFactory
* directly.
*/
private static EntityManagerFactory initEntityManagerFactory(String puName, Map properties) {
EntityManagerFactory emf;
if (properties == null) {
emf = (EntityManagerFactory) getEmfMap().get(puName);
if (emf == null) {
emf = createEntityManagerFactory(puName, null);
getEmfMap().put(puName, emf);
}
} else {
emf = createEntityManagerFactory(puName, properties);
getEmfMap().put(puName, emf);
}
return emf;
}
/*
* If EntityManager with persistence name puName is not found in Map,
* created a new one; or return the existing EntityManager of this execution directly.
*/
private static EntityManager initEntityManger(String puName,Map properties) {
EntityManager em;
if (properties == null) {
em = (EntityManager) getEmMap().get(puName);
if (em == null) {
em = createEntityManager(puName, null);
getEmMap().put(puName, em);
}
} else {
em = createEntityManager(puName, properties);
getEmMap().put(puName, em);
}
return em;
}
/*
* Create the EntityManagerFactory by persistence unit name. If persistence
* unit name not given, using the one which is defined in zk.xml
*/
private static EntityManagerFactory createEntityManagerFactory(
String puName, Map properties) {
puName = getPersistenceUnitName(puName);
EntityManagerFactory emf;
try {
if (properties == null) {
emf = Persistence.createEntityManagerFactory(puName);
log.info("EntityManagerFactory for: " + puName + " is created ");
} else {
emf = Persistence.createEntityManagerFactory(puName, properties);
log.info("EntityManagerFactory for: " + puName + " with properties "+properties + " is created ");
}
} catch (Exception ex) {
log.error("Initial EntityManagerFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
getEmfMap().put(puName, emf);
return emf;
}
/*
* Create the EntityManager by persistence unit name. If persistence unit
* name not given, using the one which is defined in zk.xml
*/
private static EntityManager createEntityManager(String puName, Map properties) {
puName = getPersistenceUnitName(puName);
EntityManager em = initEntityManagerFactory(puName, properties).createEntityManager();
return em;
}
private static WebApp getWebApp() {
WebApp app = null;
final Execution exec = Executions.getCurrent();
if (exec != null) {
final Desktop desktop = exec.getDesktop();
if (desktop != null) {
app = desktop.getWebApp();
}
}
return app;
}
private static String getPersistenceUnitName(String pu) {
if (pu == null || pu.equals("")) {
/*
* Create EntityManagerFactory by preference in zk.xml
*/
final org.zkoss.zk.ui.util.Configuration config = getWebApp().getConfiguration();
pu = config.getPreference(CONFIG, null);
}
if (pu == null) {
throw new UiException("Forget to specify the preference of "+CONFIG+" in WEB-INF/zk.xml?");
}
return pu;
}
}
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