javax.persistence.Persistence Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
//
// This source code implements specifications defined by the Java
// Community Process. In order to remain compliant with the specification
// DO NOT add / change / or delete method signatures!
//
package javax.persistence;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Map;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.spi.PersistenceProvider;
/**
* @version $Rev$ $Date$
*/
/**
* Bootstrap class that is used to obtain {@link javax.persistence.EntityManagerFactory}
* references.
*/
public class Persistence {
protected static final Set providers = new HashSet();
// Changed to the hard coded PERSISTENCE_PROVIDER value to pass signature tests.
// public static final java.lang.String PERSISTENCE_PROVIDER = PersistenceProvider.class.getName();
public static final java.lang.String PERSISTENCE_PROVIDER = "javax.persistence.spi.PeristenceProvider";
static final String PERSISTENCE_PROVIDER_PROPERTY = "javax.persistence.provider";
static final String PERSISTENCE_PROVIDER_SERVICE = "META-INF/services/"
+ PersistenceProvider.class.getName();
/**
* Create and return an EntityManagerFactory for the named persistence unit.
*
* @param persistenceUnitName The name of the persistence unit
* @return The factory that creates EntityManagers configured according to the
* specified persistence unit
*/
public static EntityManagerFactory createEntityManagerFactory(
String persistenceUnitName) {
return createEntityManagerFactory(persistenceUnitName, Collections.EMPTY_MAP);
}
/**
* Create and return an EntityManagerFactory for the named persistence unit using the
* given properties.
*
* @param persistenceUnitName The name of the persistence unit
* @param properties Additional properties to use when creating the factory. The values of
* these properties override any values that may have been configured
* elsewhere.
* @return The factory that creates EntityManagers configured according to the
* specified persistence unit.
*/
public static EntityManagerFactory createEntityManagerFactory(
String persistenceUnitName,
Map properties) {
if (properties == null) {
properties = Collections.EMPTY_MAP;
}
// start by loading a provider explicitly specified in properties. The spec
// doesn't seem to forbid providers that are not deployed as a service
Object providerName = properties.get(PERSISTENCE_PROVIDER_PROPERTY);
if (providerName instanceof String) {
EntityManagerFactory factory = createFactory(
providerName.toString(),
persistenceUnitName,
properties);
if (factory != null) {
return factory;
}
}
//If we are deployed into an OSGi environment, leverage it
Class providerClass = org.apache.servicemix.specs.locator.OsgiLocator.locate(PersistenceProvider.class);
if (providerClass != null) {
try {
PersistenceProvider provider = providerClass.newInstance();
return provider.createEntityManagerFactory(persistenceUnitName,
properties);
}
catch (Exception e) {
throw new PersistenceException("Provider error. Provider: "
+ providerName, e);
}
}
// load correctly deployed providers
ClassLoader loader = Thread.currentThread().getContextClassLoader();
try {
Enumeration providers = loader
.getResources(PERSISTENCE_PROVIDER_SERVICE);
while (providers.hasMoreElements()) {
String name = getProviderName(providers.nextElement());
if (name != null) {
EntityManagerFactory factory = createFactory(
name,
persistenceUnitName,
properties);
if (factory != null) {
return factory;
}
}
}
}
catch (IOException e) {
// spec doesn't mention any exceptions thrown by this method
}
return null;
}
static String getProviderName(URL url) throws IOException {
BufferedReader in = new BufferedReader(new InputStreamReader(
url.openStream(),
"UTF-8"));
String providerName;
try {
providerName = in.readLine();
}
finally {
in.close();
}
if (providerName != null) {
providerName = providerName.trim();
}
return providerName;
}
static EntityManagerFactory createFactory(
String providerName,
String persistenceUnitName,
Map properties)
throws PersistenceException {
Class providerClass;
try {
providerClass = Class.forName(providerName, true, Thread
.currentThread().getContextClassLoader());
}
catch (Exception e) {
throw new PersistenceException(
"Invalid or inaccessible provider class: " + providerName,
e);
}
try {
PersistenceProvider provider = (PersistenceProvider) providerClass
.newInstance();
return provider.createEntityManagerFactory(persistenceUnitName,
properties);
}
catch (Exception e) {
throw new PersistenceException("Provider error. Provider: "
+ providerName, e);
}
}
}