EJB3.0实体BEAN调用异常

[妖精的舌头]

各位老大
我用MYECLIPSE5.5开发了个测试的EJB3.0实体BEAN,发布后,做了个测试类调用,老抛出异常,都郁闷了,实在找不到问题所在,特来求教,以下是异常的节选
javax.ejb.EJBException: java.lang.RuntimeException: java.lang.ExceptionInInitializerError; nested exception is: java.lang.RuntimeException: java.lang.ExceptionInInitializerError
java.lang.RuntimeException: java.lang.ExceptionInInitializerError
at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:174)....

aused by: java.lang.ExceptionInInitializerError
at com.ejb.UmsgFacade.findById(UmsgFacade.java:66)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
....

Caused by: javax.persistence.PersistenceException: org.hibernate.HibernateException: The chosen transaction strategy requires access to the JTA TransactionManager
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:720)....

Caused by: org.hibernate.HibernateException: The chosen transaction strategy requires access to the JTA TransactionManager
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:329).....

javax.ejb.EJBException: java.lang.RuntimeException: java.lang.ExceptionInInitializerError; nested exception is: java.lang.RuntimeException: java.lang.ExceptionInInitializerError
at org.jboss.ejb3.tx.Ejb3TxPolicy.handleExceptionInOurTx(Ejb3TxPolicy.java:63).....

Caused by: java.lang.RuntimeException: java.lang.ExceptionInInitializerError
at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:174)......


Caused by: java.lang.ExceptionInInitializerError
at com.ejb.UmsgFacade.findById(UmsgFacade.java:66).....

Caused by: javax.persistence.PersistenceException: org.hibernate.HibernateException: The chosen transaction strategy requires access to the JTA TransactionManager
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:720)......

Caused by: org.hibernate.HibernateException: The chosen transaction strategy requires access to the JTA TransactionManager
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:329).......

[無名VF]

查看一下本地接口中的findById（）方法

[妖精的舌头]

本地接口和远程接口都一样呀,但我调用接口的查找方法就报以上的错误,无论是哪个方法...

[妖精的舌头]

继续
把问题顶上去/////

[IT孤儿]

你的测试类是在调用的SessionBean而你的SessionBean是在调用EntityBean，这个方式调用的是本地调用里面的数据是无法被远程调用出来的，可以在外部写个JavaBean然后在EntityBean中将数据放在这个javabean中，在将javabean放在一个ArrayList或Vector中，在远程返回的时候就返回这个集合就可以了 ,你可以试下

[feihua317]

Caused by: javax.persistence.PersistenceException: org.hibernate.HibernateException: The chosen transaction strategy requires access to the JTA TransactionManager
你的事务管理有问题？

[妖精的舌头]

谢谢各位关心，找到了问题了;因为EntityManager一直为空
而EntityManager为空的原因是
persistence unit受Java EE事务（取值JTA）管理并与之集成
此属性在Java EE环境中的默认值是JTA
而在Java SE环境中则为RESOURCE_LOCAL
而我的是java se 环境，所以设置的JTA事务出错；使用RESOURCE_LOCAL就没有问题了;
JTA 和 RESOURCE_LOCAL 两种事务管理有多大区别呢？？

<?xml version="1.0" encoding="UTF-8"?>
<persistence 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" version="1.0">

<persistence-unit name="ejbttt" transaction-type="RESOURCE_LOCAL">
<non-jta-data-source>java:/MySqlDS</non-jta-data-source>
</persistence-unit>

</persistence>