Spring 自动连线不工作，依赖项为空

我的项目目前是这样设置的：

控制器：

package com.frclocks.district.controller;

:imports:

@Path("/districts")
@Controller
public class DistrictController {

    @Autowired
    private DistrictService districtService;

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public List<District> getDistricts() {
        return districtService.getAllDistricts();
    }
}

web.xml是空的，因为我将使用JavaConfig而不是xml，也没有任何spring配置xml。我已经在网上阅读了几篇教程，这里有几篇文章，甚至浏览了我正在开发的一个项目，该项目也使用@Autowired，并且已经达到了一个极限。一些教程说要在主类中做一些事情（比如这里：），但是工作中的项目没有这样做。它有一个类似的AppConfig（对我来说有一些附加的、不必要的注释），并且没有xml配置文件。我会做错什么？我错过了什么？谢谢

编辑：空值的堆栈跟踪：

SEVERE: Servlet.service() for servlet 
[com.frclocks.config.FRCLocksApplication] in context with path 
[/frclocks] threw exception
org.jboss.resteasy.spi.UnhandledException: java.lang.NullPointerException
at org.jboss.resteasy.core.ExceptionHandler.handleApplicationException(ExceptionHandler.java:78)
at org.jboss.resteasy.core.ExceptionHandler.handleException(ExceptionHandler.java:222)
at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:195)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:457)
at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:231)
at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:137)
at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:361)
at org.jboss.resteasy.core.SynchronousDispatcher.preprocess(SynchronousDispatcher.java:140)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:217)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:227)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

Caused by: java.lang.NullPointerException
at com.frclocks.district.controller.DistrictController.getDistricts(DistrictController.java:27)
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:498)
at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140)
at org.jboss.resteasy.core.ResourceMethodInvoker.internalInvokeOnTarget(ResourceMethodInvoker.java:511)
at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTargetAfterFilter(ResourceMethodInvoker.java:402)
at org.jboss.resteasy.core.ResourceMethodInvoker.lambda$invokeOnTarget$0(ResourceMethodInvoker.java:366)
at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:361)
at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:368)
at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:340)
at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:313)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:441)
... 31 more

---

您混合了RestEasy和Spring MVC。您应该为REST端点选择这两种框架中的任何一种@Controller是Spring注释，而@Path是JAX-RS注释。两者都不起作用。目前，您的控制器是通过RestEasy调用的，它对您的Spring配置一无所知。

您将RestEasy和Spring MVC混合使用。您应该为REST端点选择这两种框架中的任何一种@Controller是Spring注释，而@Path是JAX-RS注释。两者都不起作用。目前，您的控制器是通过RestEasy调用的，而RestEasy对您的Spring配置一无所知。

您到底遇到了什么错误？哪个字段为空？对不起，应该说：控制器中的districtService为空。您是否也可以发布您得到的确切错误消息（包括stacktrace）？另外，添加

includeFilters=@ComponentScan.Filter（controller.class）

的原因是什么？由于

@Controller

是包含

@Component

的元注释，因此不需要该过滤器属性。我在堆栈跟踪/错误中添加了该属性。既然没有必要，我就把它移走。我主要是把它放进去的，因为这是我们另一个项目中的内容，我只是尝试了很多东西。你到底得到了什么错误？哪个字段为空？对不起，应该说：控制器中的districtService为空。您是否也可以发布您得到的确切错误消息（包括stacktrace）？另外，添加

includeFilters=@ComponentScan.Filter（controller.class）

的原因是什么？由于

@Controller

是包含

@Component

的元注释，因此不需要该过滤器属性。我在堆栈跟踪/错误中添加了该属性。既然没有必要，我就把它移走。我主要是把它放进去的，因为这是我们另一个项目中的内容，我只是在尝试一些东西。

package com.frclocks.config;

:imports:

@Configuration
@ComponentScan(basePackages="com.frclocks", includeFilters=@ComponentScan.Filter(Controller.class))
public class AppConfig { }

SEVERE: Servlet.service() for servlet 
[com.frclocks.config.FRCLocksApplication] in context with path 
[/frclocks] threw exception
org.jboss.resteasy.spi.UnhandledException: java.lang.NullPointerException
at org.jboss.resteasy.core.ExceptionHandler.handleApplicationException(ExceptionHandler.java:78)
at org.jboss.resteasy.core.ExceptionHandler.handleException(ExceptionHandler.java:222)
at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:195)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:457)
at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:231)
at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:137)
at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:361)
at org.jboss.resteasy.core.SynchronousDispatcher.preprocess(SynchronousDispatcher.java:140)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:217)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:227)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

Caused by: java.lang.NullPointerException
at com.frclocks.district.controller.DistrictController.getDistricts(DistrictController.java:27)
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:498)
at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140)
at org.jboss.resteasy.core.ResourceMethodInvoker.internalInvokeOnTarget(ResourceMethodInvoker.java:511)
at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTargetAfterFilter(ResourceMethodInvoker.java:402)
at org.jboss.resteasy.core.ResourceMethodInvoker.lambda$invokeOnTarget$0(ResourceMethodInvoker.java:366)
at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:361)
at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:368)
at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:340)
at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:313)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:441)
... 31 more