bean管理事务，TransactionRequiredException

Question

我有两个无状态EJB。一个使用容器管理的事务，另一个使用bean管理的事务。从容器管理的EJB中，我调用了bean管理的EJB的一个方法。

public class firstEJB{
    public void myMethod(){
        ejb.longRunningMethod();
    }

    @EJB
    private secondEJB ejb;
}


@TransactionManagement(TransactionManagementType.BEAN)
public class secondEJB {
    public void longRunningMethod(){
        while (true) {
            this.ut.begin();
            //do smth
            this.ut.commit();
        }
    }

    @Resource
    private UserTransaction ut;
}

我得到了一个错误

Caused by: javax.persistence.TransactionRequiredException: 
Exception Description: No externally managed transaction is currently active for this thread
at org.eclipse.persistence.internal.jpa.transaction.JTATransactionWrapper.throwCheckTransactionFailedException(JTATransactionWrapper.java:86)
at org.eclipse.persistence.internal.jpa.transaction.JTATransactionWrapper.checkForTransaction(JTATransactionWrapper.java:46)
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.checkForTransaction(EntityManagerImpl.java:1776)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.executeReadQuery(EJBQueryImpl.java:449)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getResultList(EJBQueryImpl.java:742)
at com.sun.enterprise.container.common.impl.QueryWrapper.getResultList(QueryWrapper.java:195)
at com.sun.enterprise.container.common.impl.TypedQueryWrapper.getResultList(TypedQueryWrapper.java:129)
at VIGS.Statistics.DataProcessor.secondEJB.longRunningMethod(secondEJB.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1052)
at org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1124)
at com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:5388)
at com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:619)
at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:800)
at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:571)
at org.jboss.weld.ejb.SessionBeanInterceptor.aroundInvoke(SessionBeanInterceptor.java:42)
at sun.reflect.GeneratedMethodAccessor69.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:861)
at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:800)
at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:571)
at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doAround(SystemInterceptorProxy.java:162)
at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:144)
at sun.reflect.GeneratedMethodAccessor68.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:861)
at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:800)
at com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:370)
at com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:5360)
at com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:5348)
at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:214)
... 42 more

我可以使用容器管理的EJB中的bean管理的事务来调用EJB的方法吗？如果是-出了什么问题？

附言:我得到了第34行的错误。下面是这行代码：

while ((lf = this.em.createNamedQuery("getNotProcessedLogFiles", LogFile.class).setMaxResults(0).setLockMode(LockModeType.PESSIMISTIC_WRITE).getResultList().get(0)) != null) {

Answer 1

每件事都很简单-在我的while循环中，我试图设置锁模式LockModeType.PESSIMISTIC_WRITE，但我们只能在事务中这样做…