org.hibernate.hql.internal.ast.QuerySyntaxException：意外令牌：* 在第 1 行附近答案

【问题标题】：org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: * near line 1org.hibernate.hql.internal.ast.QuerySyntaxException：意外令牌：* 在第 1 行附近
【发布时间】：2016-02-21 20:32:48
【问题描述】：

我必须登录我的网站

<form method="post" action="login">
    <input type="text" placeholder="Email" name="email">
    <input type="password" placeholder="Password" name="password">
    <button type="submit">Login</button>
</form>

在控制器中我有

@RequestMapping(value="/login",method=RequestMethod.POST)
    public String loginUser(@RequestParam("email") String email,
            @RequestParam("password") String password,Model model,HttpSession session){

        User persistedUser = userService.getUserByEmail(email);

        if(persistedUser!=null && persistedUser.getPassword().equals(password)){
            session.setAttribute("user", persistedUser);
            return "home";
        }else{
            model.addAttribute("error", "Incorrect username or password, Please try again!");
            return "login";
        }

    }

在 UserService 中我 getUserByEmail() as

public User getUserByEmail(String email) {
        return (User) em.createQuery("SELECT * FROM User u WHERE  u.email = :email").setParameter(email, "Not Found");
    }

当我尝试登录时，我得到了

org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: * near line 1, column 8 [SELECT * FROM com.rhcloud.giveme.entity.User u WHERE  u.email = :email]
    at org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:91)
    at org.hibernate.hql.internal.ast.ErrorCounter.throwQueryException(ErrorCounter.java:109)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:304)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:203)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:158)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:126)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:88)
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:190)
    at org.hibernate.internal.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:301)
    at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:236)
    at org.hibernate.internal.SessionImpl.createQuery(SessionImpl.java:1800)
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.createQuery(AbstractEntityManagerImpl.java:328)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:344)
    at $Proxy76.createQuery(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:291)
    at $Proxy70.createQuery(Unknown Source)
    at com.rhcloud.giveme.service.UserService.getUserByEmail(UserService.java:33)
    at com.rhcloud.giveme.service.UserService$$FastClassBySpringCGLIB$$11c5f2a8.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:649)
    at com.rhcloud.giveme.service.UserService$$EnhancerBySpringCGLIB$$79be29e2.getUserByEmail(<generated>)
    at com.rhcloud.giveme.controller.LoginController.loginUser(LoginController.java:31)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:957)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:620)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

如何为 getUserByEmail() 编写正确的查询，以便摆脱这个异常。

【问题讨论】：

标签： java hibernate spring-mvc

【解决方案1】：

你必须省略 SELECT * 部分，它是隐含的：

return (User) em.createQuery("FROM User u WHERE  u.email = :email").setParameter(email, "Not Found");

【讨论】：

好的摆脱了那个，但遇到了另一个，当我输入电子邮件和密码时，我得到java.lang.IllegalArgumentException: Parameter with that name [admin@gmail.com] did not exist，为什么会发生
我猜这是不正确的：.setParameter(email, "Not Found");。试试.setParameter("email", email);。第一个参数是查询中参数的名称；第二个参数是该参数的值。
好的，但很遗憾在return (User) em.createQuery("FROM User u WHERE u.email = :email").setParameter("email", email); 存在另一个异常'java.lang.ClassCastException: $Proxy41 cannot be cast to com.rhcloud.giveme.entity.User'。
那是因为createQuery 只是创建查询，它不执行它。你应该使用return (User) em.createQuery("FROM User u WHERE u.email = :email").setParameter("email", email).getSingleResult();。这将创建查询，执行它并获取第一个结果。