解决Websphere8.5.5上使用jpa2.1报错

1.添加两个 jar包
hibernate-entitymanager-4.3.11.Final.jar //jpa2.1
portal-kernel-5.2.3.jar //用于在HibernatePersistenceProviderResolver类中判断当前容器是否为tomcat
2. 在SessionFactory配置中，给hibernate properties配置中添加以下配置（注意，这两个配置只能在webSphere用，如果跑在tomcat中需要把这两个配置注释掉，不然会报错）

```
<prop key="hibernate.transaction.jta.platform">org.hibernate.service.jta.platform.internal.WebSphereExtendedJtaPlatform</prop> 
<prop key="hibernate.transaction.manager_lookup_class">org.hibernate.transaction.WebSphereExtendedJTATransactionLookup</prop>

```

3. 创建HibernatePersistenceProviderResolver类，并确保能被spring扫描到。

   package cn.com.agree.aweb.hibernate.dao.support;
   import org.hibernate.jpa.HibernatePersistenceProvider;
   import org.springframework.context.annotation.Configuration;
   
   import com.liferay.portal.kernel.util.ServerDetector;
   
   import javax.annotation.PostConstruct;
   import javax.persistence.spi.PersistenceProvider;
   import javax.persistence.spi.PersistenceProviderResolver;
   import javax.persistence.spi.PersistenceProviderResolverHolder;
   import java.util.Collections;
   import java.util.List;
   
   /**
    * This allows to deploy upgraded JPA and Hibernate versions to Websphere 8.5.5.x servers.
    * Has been used successfully with JPA 2.1 and Hibernate 4.3.11
    *
    * Mostly a copy of <a href="https://hibernate.atlassian.net/browse/JPA-4">https://hibernate.atlassian.net/browse/JPA-4</a>
    * Changes made to deploy in a Spring environment.
    *
    * To use: add a @DependsOn("hibernatePersistenceProviderResolver") annotation on a DatabaseConfig class
    */
   @Configuration
   public class HibernatePersistenceProviderResolver implements PersistenceProviderResolver {
       private volatile PersistenceProvider persistenceProvider = new HibernatePersistenceProvider();
   
       @Override
       public List<PersistenceProvider> getPersistenceProviders() {
           return Collections.singletonList(persistenceProvider);
       }
   
       @Override
       public void clearCachedProviders() {
           persistenceProvider = new HibernatePersistenceProvider();
       }
   
       @PostConstruct
       public void register() {
       	if(ServerDetector.isTomcat()){
       		return;
       	}
           PersistenceProviderResolverHolder.setPersistenceProviderResolver(new HibernatePersistenceProviderResolver());
       }
   }
   

4. 应用打成war，部署到webSphere上

5. 修改类加载顺序为parent last