Question

我在从我的一个bean的方法中捕获NonUniqueResultException时遇到了麻烦。

这是方法。它位于@Stateful bean内。

public Field findByTitle(String title) {
    if (title == null)
        return null;

    try {
        return entityManager
                .createQuery("SELECT f FROM Field f WHERE f.title = ?1", Field.class)
                .setParameter(1, title)
                .getSingleResult();
    } catch (NoResultException e) {
        return null;
    } 
}

简单地说，我想从另一个调用此方法的bean中捕获未经检查的NonUniqueResultException。

这是调用bean的try / catch：

try {
    Field field = fieldService.findByTitle(title);
} catch (NonUniqueResultException e) {
    LogManager.logError("Oh no!");
}

我的期望是＆＃34;哦不！＆＃34;将打印到控制台。而是打印NonUniqueResultException的整个堆栈跟踪。抓住电话永远不会被触及！

堆栈跟踪:(参考此行：.getSingleResult();）

03:39:07,228 SEVERE [javax.enterprise.resource.webcontainer.jsf.context] (default task-93) javax.ejb.EJBException: javax.persistence.NonUniqueResultException: result returns more than one elements
    at org.jboss.as.ejb3.tx.CMTTxInterceptor.handleExceptionInOurTx(CMTTxInterceptor.java:187)
    at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:277)
    at org.jboss.as.ejb3.tx.CMTTxInterceptor.required(CMTTxInterceptor.java:327)
    at org.jboss.as.ejb3.tx.CMTTxInterceptor.processInvocation(CMTTxInterceptor.java:239)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.interceptors.CurrentInvocationContextInterceptor.processInvocation(CurrentInvocationContextInterceptor.java:41)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.invocationmetrics.WaitTimeInterceptor.processInvocation(WaitTimeInterceptor.java:43)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.security.SecurityContextInterceptor.processInvocation(SecurityContextInterceptor.java:100)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.interceptors.ShutDownInterceptorFactory$1.processInvocation(ShutDownInterceptorFactory.java:64)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.interceptors.LoggingInterceptor.processInvocation(LoggingInterceptor.java:66)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ee.component.NamespaceContextInterceptor.processInvocation(NamespaceContextInterceptor.java:50)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.interceptors.AdditionalSetupInterceptor.processInvocation(AdditionalSetupInterceptor.java:54)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.ContextClassLoaderInterceptor.processInvocation(ContextClassLoaderInterceptor.java:64)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.InterceptorContext.run(InterceptorContext.java:356)
    at org.wildfly.security.manager.WildFlySecurityManager.doChecked(WildFlySecurityManager.java:636)
    at org.jboss.invocation.AccessCheckingInterceptor.processInvocation(AccessCheckingInterceptor.java:61)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.InterceptorContext.run(InterceptorContext.java:356)
    at org.jboss.invocation.PrivilegedWithCombinerInterceptor.processInvocation(PrivilegedWithCombinerInterceptor.java:80)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61)
    at org.jboss.as.ee.component.ViewService$View.invoke(ViewService.java:195)
    at org.jboss.as.ee.component.ViewDescription$1.processInvocation(ViewDescription.java:185)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61)
    at org.jboss.as.ee.component.ProxyInvocationHandler.invoke(ProxyInvocationHandler.java:73)
    at me.mitcht.myapp.core.entities.services.FieldService$$$view157.findByTitle(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.jboss.weld.util.reflection.Reflections.invokeAndUnwrap(Reflections.java:436)
    at org.jboss.weld.bean.proxy.EnterpriseBeanProxyMethodHandler.invoke(EnterpriseBeanProxyMethodHandler.java:127)
    at org.jboss.weld.bean.proxy.EnterpriseTargetBeanInstance.invoke(EnterpriseTargetBeanInstance.java:56)
    at org.jboss.weld.bean.proxy.ProxyMethodHandler.invoke(ProxyMethodHandler.java:100)
    at me.mitcht.myapp.core.entities.services.FieldService$Proxy$_$$_Weld$EnterpriseProxy$.findByTitle(Unknown Source)
    at me.mitcht.myapp.web.validators.UniqueFieldValidator.validate(UniqueFieldValidator.java:39)
    at javax.faces.component.UIInput.validateValue(UIInput.java:1164)
    at javax.faces.component.UIInput.validate(UIInput.java:982)
    at javax.faces.component.UIInput.executeValidate(UIInput.java:1248)
    at javax.faces.component.UIInput.processValidators(UIInput.java:712)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1261)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1261)
    at javax.faces.component.UIForm.processValidators(UIForm.java:253)
    at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:575)
    at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1689)
    at javax.faces.component.UIForm.visitTree(UIForm.java:371)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at javax.faces.component.UIComponent.visitTree(UIComponent.java:1700)
    at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:403)
    at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:266)
    at org.primefaces.context.PrimePartialViewContext.processPartial(PrimePartialViewContext.java:57)
    at javax.faces.context.PartialViewContextWrapper.processPartial(PartialViewContextWrapper.java:219)
    at org.omnifaces.context.OmniPartialViewContext.processPartial(OmniPartialViewContext.java:144)
    at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1193)
    at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:658)
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
    at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:81)
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:265)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchToPath(ServletInitialHandler.java:200)
    at io.undertow.servlet.spec.RequestDispatcherImpl.forwardImpl(RequestDispatcherImpl.java:193)
    at io.undertow.servlet.spec.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:106)
    at me.mitcht.myapp.web.filters.TenantFilter.doFilter(TenantFilter.java:73)
    at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60)
    at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131)
    at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84)
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
    at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
    at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:284)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:263)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:174)
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:202)
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:793)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: javax.persistence.NonUniqueResultException: result returns more than one elements
    at org.hibernate.jpa.internal.QueryImpl.getSingleResult(QueryImpl.java:539)
    at me.mitcht.myapp.core.entities.services.FieldService.findByTitle(FieldService.java:30)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.jboss.as.ee.component.ManagedReferenceMethodInterceptor.processInvocation(ManagedReferenceMethodInterceptor.java:52)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.InterceptorContext$Invocation.proceed(InterceptorContext.java:437)
    at org.jboss.as.weld.ejb.Jsr299BindingsInterceptor.doMethodInterception(Jsr299BindingsInterceptor.java:82)
    at org.jboss.as.weld.ejb.Jsr299BindingsInterceptor.processInvocation(Jsr299BindingsInterceptor.java:93)
    at org.jboss.as.ee.component.interceptors.UserInterceptorFactory$1.processInvocation(UserInterceptorFactory.java:63)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.invocationmetrics.ExecutionTimeInterceptor.processInvocation(ExecutionTimeInterceptor.java:43)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.jpa.interceptor.SBInvocationInterceptor.processInvocation(SBInvocationInterceptor.java:47)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.jpa.interceptor.SFSBInvocationInterceptor.processInvocation(SFSBInvocationInterceptor.java:57)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.stateful.StatefulSessionSynchronizationInterceptor.processInvocation(StatefulSessionSynchronizationInterceptor.java:125)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.InterceptorContext$Invocation.proceed(InterceptorContext.java:437)
    at org.jboss.weld.ejb.AbstractEJBRequestScopeActivationInterceptor.aroundInvoke(AbstractEJBRequestScopeActivationInterceptor.java:64)
    at org.jboss.as.weld.ejb.EjbRequestScopeActivationInterceptor.processInvocation(EjbRequestScopeActivationInterceptor.java:83)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ee.concurrent.ConcurrentContextInterceptor.processInvocation(ConcurrentContextInterceptor.java:45)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.InitialInterceptor.processInvocation(InitialInterceptor.java:21)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61)
    at org.jboss.as.ee.component.interceptors.ComponentDispatcherInterceptor.processInvocation(ComponentDispatcherInterceptor.java:52)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.component.stateful.StatefulComponentInstanceInterceptor.processInvocation(StatefulComponentInstanceInterceptor.java:65)
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:340)
    at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:275)
    ... 112 more

我做错了什么？

更新：试图再次抛出原因;同样的结果。

public Field findByTitle(String title) {
    if (title == null)
        return null;

    try {
        return entityManager
                .createQuery("SELECT f FROM Field f WHERE f.title = ?1", Field.class)
                .setParameter(1, title)
                .getSingleResult();
    } catch (NoResultException e) {
        return null;
    } catch (NonUniqueResultException e) {
        throw e;
    }
}

更新：这是有效的。虽然不是我喜欢它的工作方式......

try {
    Field field = fieldService.findByTitle(title);
} catch (EJBException e) {
    if (e.getCause() instanceof NonUniqueResultException) {
        LogManager.logInfo("Oh no!");
    }
    return;
}

Answer 1

从@Stateful带注释的容器托管bean调用时，您将收到EJBException，因此您需要捕获该文件（如Dmitry Ginzburg的答案中所述）。

但是，问题的更一致的方法（解决方案）是更改方法签名和实现如下：

public List<Field> findByTitle(String title) {
    if (title == null)
        return null;

    try {
        TypedQuery<Field> query =  entityManager
                .createTypedQuery("SELECT f FROM Field f WHERE f.title = ?1", Field.class);
        query.setParameter(1, title)
        return query.getResultList();
    } catch (NoResultException e) {
        return null;
    } 
}

激活/接受异常处理几乎从不是一种有效的方法。始终选择适当设计的界面，以反映您要实现的目标。

Answer 2

您可以尝试通过在查询结尾添加限制来修复它。

public Field findByTitle(String title) {
    if (title == null)
        return null;

    try {
        return entityManager
                .createQuery("SELECT f FROM Field f WHERE f.title = ?1 LIMIT 1,1", Field.class)
                .setParameter(1, title)
                .getSingleResult();
    } catch (NoResultException e) {
        return null;
    }
}

Answer 3

抛出的实际异常是javax.ejb.EJBException，所以你必须抓住它然后重新抛出原因：

try {
    ....
} catch (EJBException ex) {
    if (ex.getCause() instanceof NonUniqueResultException) {
        throw (NonUniqueResultException)ex.getCause();
    }
}

Answer 4

事实证明，因为我作为代理访问bean，所以抛出的实际异常是javax.ejb.EJBException。从堆栈跟踪中查看此行：

javax.ejb.EJBException: javax.persistence.NonUniqueResultException: result returns more than one elements

所以，（丑陋的）解决方案是捕获EJBException而不是NonUniqueResultException，然后检查原因以确保它符合我的期望：

try {
    Field field = fieldService.findByTitle(title);
} catch (EJBException e) {
    if (e.getCause() instanceof NonUniqueResultException) {
        LogManager.logInfo("Oh no!");
    }
    return;
}

这很有效，但看起来很糟糕，你可以说它只是糟糕的设计。

因此，我选择使用建议的MWiesner解决方案返回结果的Collection而不只是一个结果。这样我就可以简单地检查集合的大小。如果它大于1，显然结果不是唯一的。

NonUniqueResultException未被捕获

4 个答案: