设置默认处理程序后导航到未映射的网址时出错

Question

我正在使用 Spring MVC 6.0.11，Java 19。我在基于 java 的配置文件中设置了一个 defaultHandler，如下所示

@Bean
public RequestMappingHandlerMapping handlerMapping() {
    RequestMappingHandlerMapping handlerMapping = new RequestMappingHandlerMapping();

    ErrorController ec = new ErrorController();
    handlerMapping.setDefaultHandler("errorController");
    return handlerMapping;
        
}

错误控制器是：

package com.sp.controllers;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping(value="/error")
public class ErrorController{
    
    @ResponseBody
    @GetMapping
    public String error() {
        
        System.out.println("test test test");
        return "test test test";
    }

}

当我导航到由 ErrorController 处理的未映射网页时，出现以下错误：

jakarta.servlet.ServletException：没有处理程序的适配器 [com.sp.controllers.ErrorController@14a028ca]：DispatcherServlet 配置需要包含支持此处理程序的 HandlerAdapter org.springframework.web.servlet.DispatcherServlet.getHandlerAdapter(DispatcherServlet.java:1316) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1064) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:974) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903) jakarta.servlet.http.HttpServlet.service(HttpServlet.java:564) org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)

我尝试使用RequestMappingHandlerMapping.setDefaultHandler()设置defaultHandler。我本以为只要在没有显式映射的情况下在 Web 应用程序中点击 URL，就会显示从 ErrorController.error() 返回的消息，但我却收到了错误消息。

Answer 1

@豆豆 公共 RequestMappingHandlerMapping handlerMapping() { RequestMappingHandlerMapping handlerMapping = new RequestMappingHandlerMapping();

ErrorController ec = new ErrorController();

handlerMapping.setDefaultHandler("errorController"); //ec not used 
return handlerMapping;
    

}