在做SpringMVC 测试时发现在配置完全正确
0.相关JAR包完全导入，Tomcat启动完全成功
1.配置有扫描
<!-- 处理静态资源 --> <mvc:default-servlet-handler/> <!-- Configures the annotation-driven Spring MVC Controller programming model. Note that this tag works in Web MVC only, not in Portlet MVC! See org.springframework.web.servlet.config.annotation.EnableWebMvc javadoc for details on code-based alternatives to enabling annotation-driven Spring MVC support. --> <mvc:annotation-driven /> <!-- 配置包扫描器，扫描@Controller注解的类 --> <context:component-scan base-package="com.taotao.controller.*"/>2.在注解生效，且相应处理该次请求的Controller 已经被实例化（通过重写构造方法发现）
3.相关方法有RequestMapping注解（method字段与对应请求方式相符合）
@RequestMapping(value = "/item/cat/list", method = {RequestMethod.POST}) @ResponseBody public List<EasyUITreeNode> list(@RequestParam(value = "id", defaultValue = "0") long parentId) { System.out.println("进入了这个方法"); return itemCatService.listCat(parentId); } 4. 相应控制器上看看有没有 @RequestMapping 注解，有并在其中写上了相应uri路劲（如果你的控制器没有写上，而是写成了@Controller("/item/cat") 那么肯定是失败的，我就是心急没注意看到了这一步就解决了）看看是不是
后端出现的错误：
2017-08-31 21:50:18,895 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.DispatcherServlet] - DispatcherServlet with name 'spring-mvc' processing GET request for [/item/cat/list] 2017-08-31 21:50:18,895 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping] - Looking up handler method for path /item/cat/list 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping] - Did not find handler method for [/item/cat/list] 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.handler.SimpleUrlHandlerMapping] - Matching patterns for request [/item/cat/list] are [/**] 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.handler.SimpleUrlHandlerMapping] - URI Template variables for request [/item/cat/list] are {} 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.handler.SimpleUrlHandlerMapping] - Mapping [/item/cat/list] to HandlerExecutionChain with handler [org.springframework.web.servlet.resource.DefaultServletHttpRequestHandler@1697861] and 1 interceptor 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.DispatcherServlet] - Last-Modified value for [/item/cat/list] is: -1 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.DispatcherServlet] - Null ModelAndView returned to DispatcherServlet with name 'spring-mvc': assuming HandlerAdapter completed request handling 2017-08-31 21:50:18,896 [http-bio-8080-exec-3] DEBUG [org.springframework.web.servlet.DispatcherServlet] - Successfully completed request
页面出现的错误：
HTTP Status 404 - /item/cat/list type Status report message /item/cat/list description The requested resource is not available.