如何解决SpringBoot中的405 Method Not Allowed错误？

我在Postman中访问URL http://localhost:8080/registration 时，期望收到消息"Works"，但实际遇到405 Method Not Allowed错误。尝试过替换@Controller为@RestController、修改部分注解均未成功，使用IntelliJ调试也未获得有效信息，现寻求解决方法。

相关代码 #

WebSecurityConfig类 #

package com.example.finalVersionBookProject.security.config;

import com.example.finalVersionBookProject.appuser.AppUserService;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;

@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    private final AppUserService appUserService;
    private final BCryptPasswordEncoder bCryptPasswordEncoder;
    
    public WebSecurityConfig(AppUserService appUserService, BCryptPasswordEncoder bCryptPasswordEncoder) {
        this.appUserService = appUserService;
        this.bCryptPasswordEncoder = bCryptPasswordEncoder;
    }
}

Registration类 #

package com.example.finalVersionBookProject.registration;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;

@Controller
@RequestMapping(path = "/registration")
public class Registration {
    private RegistrationService registrationService;

    @PostMapping()
    public String register(@RequestBody RegistrationRequest request) {
        return registrationService.register(request);
    }
}

RegistrationService类 #

package com.example.finalVersionBookProject.registration;

import org.springframework.stereotype.Service;

@Service
public class RegistrationService {
    public String register(RegistrationRequest request) {
        return "works";
    }
}

解决方法 #

1. 核对请求方法匹配性
   你的Registration类仅定义了@PostMapping接口，务必确认Postman中使用的是POST请求，而非GET、PUT等其他方法。若需支持GET请求，可添加@GetMapping注解的对应方法。

2. 修正控制器注解与返回逻辑
   使用@Controller时，返回的字符串默认会被解析为视图名称，而非直接作为响应体返回。要返回纯文本"works"，有两种可行方式：

   • 直接将@Controller替换为@RestController（该注解包含@Controller和@ResponseBody，自动将返回值转为响应体）；
   • 保留@Controller，在register方法上添加@ResponseBody注解。

3. 完善Spring Security配置
   你的WebSecurityConfig类未实现configure(HttpSecurity http)方法，默认会拦截所有请求并要求认证。需添加配置允许/registration路径匿名访问：

   @Override
   protected void configure(HttpSecurity http) throws Exception {
       http.csrf().disable()
           .authorizeRequests()
           .antMatchers("/registration")
           .permitAll()
           .anyRequest()
           .authenticated();
   }
   
   @Override
   protected void configure(AuthenticationManagerBuilder auth) throws Exception {
       auth.authenticationProvider(daoAuthenticationProvider());
   }
   
   @Bean
   public DaoAuthenticationProvider daoAuthenticationProvider() {
       DaoAuthenticationProvider provider = new DaoAuthenticationProvider();
       provider.setPasswordEncoder(bCryptPasswordEncoder);
       provider.setUserDetailsService(appUserService);
       return provider;
   }
   

   这段配置关闭了CSRF（Postman测试可先关闭，若后续对接表单可再开启），允许/registration路径无需认证即可访问，同时配置了DaoAuthenticationProvider完成用户认证逻辑。

4. 检查请求体格式
   @RequestBody注解要求请求体为JSON格式，需确认Postman中请求头设置了Content-Type: application/json，且请求体符合RegistrationRequest类的结构，例如：

   {
       "username": "test",
       "password": "123456"
   }
   

   若未定义RegistrationRequest类，需先创建该实体类，包含对应字段及getter/setter方法。

内容的提问来源于stack exchange，提问作者Dave Patel