我无法在Aspect中@Autowire
服务层实例。在Aspect中,对@Autowired
bean的引用为NULL,并引发NullPointerException
。任何帮助都感激不尽。我想,我搞砸了配置。
以下是我的servlet-context.xml
:
<!-- Activates various annotations to be detected in bean classes -->
<context:annotation-config />
<context:spring-configured />
<!-- Scans the classpath of this application for @Components to deploy as beans -->
<context:component-scan base-package="xx.yy" />
<!-- an @AspectJ aspect will be interpreted as an aspect by Spring AOP and beans in the context will be advised accordingly -->
<aop:aspectj-autoproxy />
<beans:bean id="loggingAspect" class="xx.yy.aop.aspects.LoggingAspect" />
<beans:bean id="authenticationAspect" class="xx.yy.aop.aspects.AuthenticationAspect" />
<!-- Enables the Spring MVC @Controller programming model -->
<annotation-driven />
以下是我的观点:
@Configurable
@Component
@Aspect
public class AuthenticationAspect {
private static final Logger logger = LoggerFactory.getLogger(AuthenticationAspect.class);
@Autowired
private LoginService loginService;
//....
}
这是我的 Controller ,使用上面定义的
@Authentication
注释:@Controller
@RequestMapping("/user")
public class UsersController {
@Autowired
private UserService userService;
@Authenticate
@RequestMapping(value="/{userId}/profile", method=RequestMethod.GET)
public String displayUser(WebRequest webRequest, @PathVariable("userId") String userId, Model model) {
User user = userService.findUser(Long.valueOf(userId));
model.addAttribute("user", user);
model.addAttribute("AccordionMenuTab","5");
model.addAttribute("selectedLink","profile");
return "profile";
}
我收到以下异常:
Oct 8, 2011 3:12:48 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet appServlet threw exception
java.lang.NullPointerException
at xx.yy.controller.UsersController.displayUser_aroundBody1$advice(UsersController.java:28)
at xx.yy.controller.UsersController.displayUser(UsersController.java:1)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:662)
最佳答案
参见this piece of the documentation:
<bean id="profiler" class="com.xyz.profiler.Profiler"
factory-method="aspectOf" />