JAVA控制器中的Spring框架NullPointerException
我有这个空指针。当我调试代码时,我看到u为null,model为{}。我猜模型是{},因为出现了异常,但我不知道为什么在用户上有null 控制器JAVA控制器中的Spring框架NullPointerException,java,spring,Java,Spring,我有这个空指针。当我调试代码时,我看到u为null,model为{}。我猜模型是{},因为出现了异常,但我不知道为什么在用户上有null 控制器 @Controller @RequestMapping(value = "/home") public class HomeController { @Autowired private DomainManager domainManager; @RequestMapping(method = RequestMethod.G
@Controller
@RequestMapping(value = "/home")
public class HomeController {
@Autowired
private DomainManager domainManager;
@RequestMapping(method = RequestMethod.GET)
public String showPage(HttpSession session, Model model) {
User u = (User) session.getAttribute(User.SESSION_PROPERTY);
Domain domain = domainManager.getDomain(u.getDomainId());
Quota used = domainManager.getQuotaUsage(u.getDomainId());
boolean active = domainManager.isDomainActive(u.getDomainId());
model.addAttribute("domain", domain);
model.addAttribute("active", active);
model.addAttribute("used", used);
return "home";
}
堆栈
java.lang.NullPointerException
bg.abv.saas.admin.controller.HomeController.showPage(HomeController.java:27)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:497)
org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
会话属性中没有名为User.SESSION\u属性的变量。模型必须是
{}
,因为您还没有添加任何内容。@Ken Bekov SESSION\u属性是用户类中的一个静态字段,它不是空的或null。我的意思是,如果user.SESSION\u属性
包含“some string”
,则会话中没有名为“some string”
的属性。您必须弄清楚-为什么。您的用户没有进行身份验证,因此您的密码将返回null@kakashi当我无法打开jsp文件时,如何对用户进行身份验证?