错误创建EntityManager对象

我试图创建一个持久性的EntityManager对象，我无法创建EntityManager对象。请在下面找到示例代码：错误创建EntityManager对象

EntityManagerFactory emf = Persistence.createEntityManagerFactory("Draco-PU"); 
EntityManager em = emf.createEntityManager();

我也在persistence.xml文件中定义了持久单元名称。

<persistence-unit name="Draco-PU" >

持久化XML被定义如下：

<?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="Draco-PU" > 
<provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider> 
<jta-data-source>DracoDataSource</jta-data-source> 
<non-jta-data-source>DracoUnmanagedDataSource</non-jta-data-source> 
<class>dk.tdc.soa.smo.draco.db.model.DslServiceEntity</class> 
<class>dk.tdc.soa.smo.draco.db.model.DslServiceCatalogEntity</class> 
<class>dk.tdc.soa.smo.draco.db.model.History</class> 
<class>dk.tdc.soa.smo.draco.db.model.ConfigEntity</class> 
<properties> 
    <property name="openjpa.Log" value="DefaultLevel=WARNING, Runtime=WARNING, Tool=WARNING, SQL=WARNING" /> 
    <!-- <property name="openjpa.jdbc.DBDictionary" value="org.apache.openjpa.jdbc.sql.OracleDictionary" /> -->  
    <property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema(ForeignKeys=true)" /> 
</properties> 
</persistence-unit> 
</persistence>

面临的错误是：

javax.persistence.PersistenceException: No Persistence provider for EntityManager 
named Draco-PU: Provider named kodo.persistence.PersistenceProviderImpl threw 
expected exception at create EntityManagerFactory: 
org.apache.openjpa.persistence.PersistenceException<openjpa-1.1.1-SNAPSHOT- 
r422266:891341 fatal general error> 
org.apache.openjpa.persistence.PersistenceException: There was an error when invoking 
the static newInstance method on the named factory class 
"kodo.jdbc.kernel.KodoJDBCBrokerFactory".

请帮帮忙！

来源

2012-10-19 San

请上传你的错误，否则我们将无法帮助！ – ppeterka

@ppeterka错误已张贴。请检查 – San

我已经在持久定义的持久性提供xml.But错误依然存在 – San

你声明persistence.xml中你的“持久性单元”元素中的“提供者”元素？它应该是这个样子：

<persistence-unit name="Draco-PU"> 
    <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider> 
</persistence-unit>

来源

2012-10-20 05:01:04 Templar

是!我已经在persistence xml中定义了它，但错误仍然存在 – San

创建你的WEB-INF文件夹内的一个结构：类/ META-INF，把你的persistence.xml文件中并重新启动服务器。

的Weblogic会在构建目录中的文件。

来源

2013-11-28 00:03:39 psantamaria

错误创建EntityManager对象

回答

相关问题