UnsatisfiedDependencyException：创建名称为“registrationController”的 bean 时出错

Question

I am completely new to spring-boot and I am trying to create a registration backend, but there exist an error that confused me. I looked through a lot of similar questions, but no one answer to them can't help me.

WARN 18732 --- [ main] ConfigServletWebServerApplicationContext: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registrationController': Unsatisfied dependency expressed through field 'registrationService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registrationService': Unsatisfied dependency expressed through field 'accApplMapper'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.example.demo.mapper.AccApplMapper' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

Description: Field accApplMapper in com.example.demo.service.RegistrationService required a bean of type > 'com.example.demo.mapper.AccApplMapper' that could not be found. The injection point has the following annotations: - @org.springframework.beans.factory.annotation.Autowired(required=true) Action: Consider defining a bean of type 'com.example.demo.mapper.AccApplMapper' in your configuration.

RegistrationController.java

package com.example.demo.controller;

import com.example.demo.result.Result;
import com.example.demo.pojo.NewUser;
import org.springframework.beans.factory.annotation.Autowired;
import com.example.demo.service.RegistrationService;


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

@Controller
public class RegistrationController {
    @Autowired
    RegistrationService registrationService;
    @CrossOrigin
    @PostMapping(value = "api/registration")
    @ResponseBody
    public Result registration(@RequestBody NewUser user) {
        System.out.println(user.toString());
        if(user!=null && user.getCompanyName()!=null) {
            int insert = registrationService.addAcctAppl(user.getCompanyName());
            return insert>=0 ? new Result(200) : new Result(500);
          }
          else {
            return new Result(400);
         }
    }

}

RegistrationService.java

package com.example.demo.service;

import com.example.demo.mapper.AccApplMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class RegistrationService {
    @Autowired
    private AccApplMapper accApplMapper;
    
    public int addAcctAppl(String CompanyName) {
        return accApplMapper.addAcctAppl(CompanyName);
    }
}

AccApplMapper.java

package com.example.demo.mapper;


import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;


@Mapper
public interface AccApplMapper {
    @Insert("INSERT INTO ACCT_APPL(ENG_COMP_NAME) VALUES(#{CompanyName}")
    public int addAcctAppl(@Param("CompanyName") String CompanyName);
}
 

Answer 1

@Mapper is not a spring bean annotation, you need to use @MapperScan(basepackages="your mapper package location") annotation on a class with a annotation @Configuration (usually you could use @MapperScan on the Springboot main class) to enable spring to register @Mapper classes as bean.