Spring Boot创建'requestMappingHandlerMapping' Bean报错：请求映射歧义

你碰到的这个Ambiguous mapping错误其实很好解决，核心问题出在你对@RequestMapping注解的使用上——你错误地用了name属性来指定请求URL路径，但name属性的作用只是给这个映射起一个描述性的名称，根本不是用来定义路径的！

当你没有给@RequestMapping指定value或者path属性时，Spring会默认把请求路径设为空字符串。这就导致你控制器里的newServer、getServer等多个GET方法，全都映射到了同一个空路径上，自然就触发了映射冲突的错误。

修改后的正确代码 #

只需要把每个@RequestMapping里的name替换成value（或者path，两者功能完全一致）就行：

@Controller
public class CSPServerController {
    @Autowired
    ServerService serverService;
    @Autowired
    AuditLogService auditLogService;

    @RequestMapping(value = "/servers", method = RequestMethod.GET)
    @PreAuthorize("hasRole(T(com.nathanenglish.serverlldmanagementtool.config.GlobalConfig).RoleReadOnly)")
    public String loadServers(Model model){
        model.addAttribute("servers",serverService.getAll());
        return "servers";
    }

    @RequestMapping(value = "/servers/new", method = RequestMethod.GET)
    @PreAuthorize("hasRole(T(com.nathanenglish.serverlldmanagementtool.config.GlobalConfig).RoleEdit)")
    public String newServer(Model model){
        model.addAttribute("server", new Server());
        model.addAttribute("auditLog", new AuditLog());
        return "server";
    }

    @RequestMapping(value = "/servers/{id}", method = RequestMethod.GET)
    @PreAuthorize("hasRole(T(com.nathanenglish.serverlldmanagementtool.config.GlobalConfig).RoleEdit)")
    public String getServer(@PathVariable Long id, Model model){
        model.addAttribute("server", serverService.getById(id));
        model.addAttribute("auditLog", new AuditLog());
        return "server";
    }

    @RequestMapping(value = "/servers/save", method = RequestMethod.POST)
    @PreAuthorize("hasRole(T(com.nathanenglish.serverlldmanagementtool.config.GlobalConfig).RoleEdit)")
    public String saveServer(Model model, @Valid Server server, @Valid AuditLog auditLog, BindingResult bindingResult){
        if(bindingResult.hasErrors()){
            return "server";
        }
        serverService.save(server);
        auditLogService.save(auditLog);
        return "redirect:/servers";
    }

    @RequestMapping(value = "/servers/delete/{id}", method = RequestMethod.GET)
    @PreAuthorize("hasRole(T(com.nathanenglish.serverlldmanagementtool.config.GlobalConfig).RoleEdit)")
    public String deleteServer(@PathVariable Long id, Model model){
        serverService.deleteByID(id);
        return "redirect:/servers";
    }
}

额外优化建议 #

Spring 4.3及以上版本推荐使用更简洁的HTTP方法专用注解，比如@GetMapping、@PostMapping，这样可以省略method属性，让代码更清爽：

// 替代@RequestMapping(value = "/servers", method = RequestMethod.GET)
@GetMapping("/servers")

内容的提问来源于stack exchange，提问作者Nathan English