javax.servlet.ServletException
exception  

javax.servlet.ServletException:   #{UserLogin.userLogin}:   javax.faces.el.EvaluationException:   java.lang.ClassCastException:   java.lang.String
javax.faces.webapp.FacesServlet.service(FacesServlet.java:209)


root   cause  

javax.faces.FacesException:   #{UserLogin.userLogin}:   javax.faces.el.EvaluationException:   java.lang.ClassCastException:   java.lang.String
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:78)
javax.faces.component.UICommand.broadcast(UICommand.java:312)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:267)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:381)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:75)
com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)



------解决方案--------------------
FacesServlet.java的209行，强制类型转换错误
------解决方案--------------------
javax.faces.FacesException: #{UserLogin.userLogin}: javax.faces.el.EvaluationException: java.lang.ClassCastException: java.lang.String
看看UserLogin.userLogin
------解决方案--------------------
ding....