Spring Boot 应用程序中没有类型 'testgroup.private_clinic.dao.PatientDAO' 的合格 bean

Question

我正在开发 crud 应用程序，在使用 springboot 时遇到困难，启动失败。这是我得到的：

20764 WARNING [main] --- org.springframework.context.annotation.AnnotationConfigApplicationContext: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'patientServiceImpl': Unsatisfied dependency expressed through method 'setPatientDAO' parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'testgroup.private_clinic.dao.PatientDAO' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}

项目结构截图：

型号：

package testgroup.private_clinic.model;

import javax.persistence.*;

@Entity
@Table(name="Patients")
public class Patient {

    @Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    int id;
    @Column(name="patient_name")
    String name;
    @Column(name = "patient_surname")
    String surname;
    @Column(name = "patient_patronimic")
    String patronimic;
    @Column(name="adress")
    String adress;
    @Column(name = "status")
    String status;
    @Column(name="diagnosis")
    String diagnosis;

//+getters and setters

控制器：

package testgroup.private_clinic.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.ModelAndView;
import testgroup.private_clinic.model.Patient;
import testgroup.private_clinic.service.PatientService;

import java.util.List;

@RestController
public class PatientController {

    PatientService patientService;

    @Autowired
    public void setPatientService(PatientService patientService){
        this.patientService = patientService;
    }

    @RequestMapping(method = RequestMethod.GET)
    public ModelAndView allPatients(){
        List<Patient> patients = patientService.allPatients();
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("patients");
        modelAndView.addObject("patientList", patients);
        return modelAndView;
    }

    @RequestMapping(value= "/edit{id}", method = RequestMethod.GET)
    public ModelAndView editPage(@PathVariable("id") int id){
        Patient patient = patientService.getByID(id);
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("editPage");
        modelAndView.addObject("patient", patient);
        return modelAndView;
    }

    @RequestMapping(value="/edit", method = RequestMethod.POST)
    public ModelAndView editPatient(@ModelAttribute("patient") Patient patient){
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("redirect:/");
        patientService.edit(patient);
        return modelAndView;
    }
}

存储库：

package testgroup.private_clinic.dao;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import testgroup.private_clinic.model.Patient;

import javax.transaction.Transactional;
import java.util.*;


@Repository
public class PatientDAOImpl implements PatientDAO {

    SessionFactory sessionFactory;

    @Autowired
    public void setSessionFactory(SessionFactory sessionFactory){
        this.sessionFactory = sessionFactory;
    }

    @Override
    @Transactional
    public List<Patient> allPatients() {
        Session session = sessionFactory.getCurrentSession();
        return session.createQuery("from Patient").list();
    }

    @Override
    @Transactional
    public void add(Patient patient) {
        Session session = sessionFactory.getCurrentSession();
        session.persist(patient);
    }

    @Override
    @Transactional
    public void delete(Patient patient) {
        Session session = sessionFactory.getCurrentSession();
        session.delete(patient);
    }

    @Override
    @Transactional
    public void edit(Patient patient) {
        Session session = sessionFactory.getCurrentSession();
        session.update(patient);
    }

    @Override
    @Transactional
    public Patient getByID(int id) {
        Session session = sessionFactory.getCurrentSession();
        return session.get(Patient.class, id);
    }
}

服务：

package testgroup.private_clinic.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import testgroup.private_clinic.model.Patient;
import testgroup.private_clinic.dao.PatientDAO;

import javax.transaction.Transactional;
import java.util.List;

@Service
public class PatientServiceImpl implements PatientService{

    PatientDAO patientDAO;

    @Autowired
    public void setPatientDAO(PatientDAO patientDAO){
        this.patientDAO = patientDAO;
    }


    @Transactional
    @Override
    public List<Patient> allPatients() {
        return patientDAO.allPatients();
    }

    @Transactional
    @Override
    public void add(Patient patient) {
        patientDAO.add(patient);

    }

    @Transactional
    @Override
    public void delete(Patient patient) {
        patientDAO.delete(patient);
    }

    @Transactional
    @Override
    public void edit(Patient patient) {
        patientDAO.edit(patient);
    }

    @Transactional
    @Override
    public Patient getByID(int id) {
        return patientDAO.getByID(id);
    }
}

主要class:

package testgroup.private_clinic.service;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;




@SpringBootApplication
public class SpringBootClass {
    public static  void main(String[] args){
        SpringApplication.run(testgroup.private_clinic.service.SpringBootClass.class, args);
    }
}

Answer 1

Spring Boot使用class路径组件扫描的意思，你的入口点class就是SpringBootClass 将扫描其 class 路径中的所有 bean，除非您将其配置为不这样做。

查看您的项目结构，SpringBootClass 在 testgroup.private_clinic.service 包下，因此 Spring Boot 只会扫描这个包中的 bean，它只会找到 PatientServiceImpl 然而，在将它注入应用程序上下文之前，它需要先注入它的依赖项 PatientDAO 不是 testgroup.private_clinic.service 包的一部分，因此解释了您的错误。

您有两种选择来解决此问题：

将您的 SpringBootClass 移动到基本包 testgroup.private_clinic - 这将对这个包及其子包下的所有组件进行 Spring 引导扫描（例如， 服务，dao）
在你的 SpringBootClass 上使用 @ComponentScan 并在那里定义基础包你想扫描豆子。

@ComponentScan(basePackages = "testgroup.private_clinic")

感谢和欢呼！

Spring Boot 应用程序中没有类型 'testgroup.private_clinic.dao.PatientDAO' 的合格 bean

No qualifying bean of type 'testgroup.private_clinic.dao.PatientDAO' available in SpringBoot Application

dao

javabeans

spring-bean

spring-boot