如何通过自定义插件 portlet 中的自定义查找器获取 liferay 实体？

我们如何使用自定义 SQL 通过自定义查找器获取 liferay 实体？

1. Following is my sql query written in default.xml (_{I have trimmed down the query to the bare minimum so that the logic remains simple. Since it included a few functions and joins we couldn't use DynamicQuery API} ):

   SELECT
       grp.*
   FROM
       Group_
   WHERE
       site = 1
       AND active_ = 1
       AND type_ <> 3
   

2. 相关代码在MyCustomGroupFinderImpl.java:

   Session session = null;
   
   try {
       session = openSession();
   
       // fetches the query string from the default.xml
       String sql = CustomSQLUtil.get(FIND_ONLY_ACTIVE_SITES);
   
       SQLQuery sqlQuery = session.createSQLQuery(sql);
   
       sqlQuery.addEntity("Group_", GroupImpl.class);
       // sqlQuery.addEntity("Group_", PortalClassLoaderUtil.getClassLoader().loadClass("com.liferay.portal.model.impl.GroupImpl"));
   
       return (List<Group>) QueryUtil.list(sqlQuery, getDialect(), 0, QueryUtil.ALL_POS);
   }
   catch (Exception e) {
       throw new SystemException(e);
   }
   finally {
       closeSession(session);
   }
   

上面的代码将不起作用GroupImpl类存在于portal-impl.jar并且此 jar 不能在自定义 portlet 中使用。

我也尝试过使用sqlQuery.addEntity("Group_", PortalClassLoaderUtil.getClassLoader().loadClass("com.liferay.portal.model.impl.GroupImpl"))
但上面的代码抛出异常：

com.liferay.portal.kernel.exception.SystemException:
    com.liferay.portal.kernel.dao.orm.ORMException:
        org.hibernate.MappingException:
            Unknown entity: com.liferay.portal.model.impl.GroupImpl

但是相同的代码适用于我们的自定义实体，如果我们编写sqlQuery.addEntity("MyCustomGroup", MyCustomGroupImpl.class);.

Thanks

我从Liferay 论坛帖子 http://www.liferay.com/community/forums/-/message_boards/view_message/7158040#_19_message_7166735那个而不是session = openSession();我们需要从中获取会话liferaySessionFactory如下使其工作：

// fetch liferay's session factory
SessionFactory sessionFactory = (SessionFactory) PortalBeanLocatorUtil.locate("liferaySessionFactory");

Session session = null;

try {
    // open session using liferay's session factory
    session = sessionFactory.openSession();

    // fetches the query string from the default.xml
    String sql = CustomSQLUtil.get(FIND_ONLY_ACTIVE_SITES);

    SQLQuery sqlQuery = session.createSQLQuery(sql);

    // use portal class loader, since this is portal entity
    sqlQuery.addEntity("Group_", PortalClassLoaderUtil.getClassLoader().loadClass("com.liferay.portal.model.impl.GroupImpl"));

    return (List<Group>) QueryUtil.list(sqlQuery, getDialect(), 0, QueryUtil.ALL_POS);
}
catch (Exception e) {
    throw new SystemException(e);
}
finally {
    sessionFactory.closeSession(session); // edited as per the comment on this answer
    // closeSession(session);
}

希望这对 stackoverflow 上的人有帮助，我也找到了一个不错的tutorial http://www.liferaysavvy.com/2013/02/getting-data-from-multiple-tables-in.html关于custom-sql，它也使用相同的方法。