无法使用JPA 2.0 Eclipselink预部署PersistenceUnit

Question

我正在使用EclipseLink 2.2.0开发基于Java EE的Web应用程序。

此应用程序部署在Tomcat 7.0.14下

我收到org.eclipse.persistence.exceptions.EntityManagerSetupException，其说明文字如下：

  

无法在无效状态下预部署PersistenceUnit [NamePU] [Undeployed]

这是persistence.xml：

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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_2_0.xsd">
    <persistence-unit name="StatsPU" transaction-type="RESOURCE_LOCAL">
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <class>com.db.persistence.SessionLog</class>
        <class>com.db.persistence.UserData</class>
        <exclude-unlisted-classes>true</exclude-unlisted-classes>
        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:jtds:sqlserver://0.0.0.0:1433/Stats"/>
            <property name="javax.persistence.jdbc.password" value="password"/>
            <property name="javax.persistence.jdbc.driver" value="net.sourceforge.jtds.jdbc.Driver"/>
            <property name="javax.persistence.jdbc.user" value="sa"/>
            <property name="eclipselink.weaving" value="static"/>
        </properties>
    </persistence-unit>

    <persistence-unit name="ServicesPU" transaction-type="RESOURCE_LOCAL">
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <class>com.db.persistence.UserSession</class>
        <exclude-unlisted-classes>true</exclude-unlisted-classes>
        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:jtds:sqlserver://0.0.0.0:1433/App"/>
            <property name="javax.persistence.jdbc.password" value="password"/>
            <property name="javax.persistence.jdbc.driver" value="net.sourceforge.jtds.jdbc.Driver"/>
            <property name="javax.persistence.jdbc.user" value="sa"/>
            <property name="eclipselink.weaving" value="static"/>
        </properties>
    </persistence-unit>
</persistence>

在创建EntityManagerFactory期间发生错误。

我不太清楚为什么会发生异常，而且我在EclipseLink的文档中找不到信息。有什么想法吗？