找回 Controller 、Service 、Model、 Repository熟悉的感觉
- Controller: 请求的入口（路由分发映射的文件）
- Service: 业务逻辑处理与数据仓库交互
- Model: 实体与数据库中的表对应
- Repository: 数据仓库
- Mac
- mysql5.8
- Idea
- jdk1.8
- Maven 3.8.6
pom.xml
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>6.0.6</version> <!-- 不加版本号 application.yml配置文件，数据库驱动爆红 -->
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
application.yml
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/test
username: root
password: root
jpa:
hibernate:
ddl-auto: create
show-sql: true
models/UserModel 实体类 - 对应数据库中的数据表
package com.learn.demo.models;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
@Entity
public class UserModel {
@Id
@GeneratedValue
private Integer id;
private String username;
private String password;
public UserModel() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
dao/UserRepository
package com.learn.demo.dao;
import com.learn.demo.models.UserModel;
import org.springframework.data.jpa.repository.JpaRepository;
public interface UserRepository extends JpaRepository<UserModel, Integer> {
}
service/UserService 接口
package com.learn.demo.service;
import com.learn.demo.models.UserModel;
import java.util.List;
import java.util.Optional;
public interface UserService {
UserModel createService(String username, String password);
Optional<UserModel> getUserByIdService(Integer id) throws Exception;
List<UserModel> listService();
UserModel updateUserById(Integer id, String username, String password) throws Exception;
boolean delUserByIdService(Integer id) throws Exception;
}
service/Impl/UserServiceImpl 接口的实现
package com.learn.demo.service.Impl;
import com.learn.demo.dao.UserRepository;
import com.learn.demo.models.UserModel;
import com.learn.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
import java.util.Optional;
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserRepository userRepository;
/** * * @param username * @param password * @return */
public UserModel createService(String username, String password) {
UserModel userModel = new UserModel();
userModel.setUsername(username);
userModel.setPassword(password);
return userRepository.save(userModel);
}
/** * * @param id * @return * @throws Exception */
public Optional<UserModel> getUserByIdService(Integer id) throws Exception{
if (id == null) {
throw new IllegalArgumentException("Parameter id can't be null");
}
return userRepository.findById(id);
}
/** * * @return */
public List<UserModel> listService() {
return userRepository.findAll();
}
/** * * @param id * @param username * @param password * @return * @throws Exception */
public UserModel updateUserById(Integer id, String username, String password) throws Exception {
if (id == null) {
throw new IllegalArgumentException("Parameter id can't be null");
}
Optional<UserModel> optional = userRepository.findById(id);
if (optional.isPresent()) {
UserModel userModel = optional.get();
userModel.setUsername(username);
userModel.setPassword(password);
return userRepository.save(userModel);
}
return null;
}
/** * * @param id * @return * @throws Exception */
public boolean delUserByIdService(Integer id) throws Exception {
if (id == null) {
throw new IllegalArgumentException("Parameter id can't be null");
}
userRepository.deleteById(id);
return true;
}
}
controller/UserController
package com.learn.demo.controller;
import com.learn.demo.models.UserModel;
import com.learn.demo.service.Impl.UserServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
import java.util.Optional;
@RestController
public class UserController {
@Autowired
private UserServiceImpl userServiceImpl;
/** * 创建用户 * @param username * @param password * @return */
@PostMapping("/create")
public UserModel create(@RequestParam("username") String username,
@RequestParam("password") String password) {
return userServiceImpl.createService(username, password);
}
/** * 通过ID获取用户信息 * @param id * @return */
@GetMapping("/get/user/{id}")
public Optional<UserModel> getUserById(@PathVariable("id") Integer id) throws Exception{
return userServiceImpl.getUserByIdService(id);
}
/** * 用户列表 * @return */
@GetMapping("/user/list")
public List<UserModel> list() {
return userServiceImpl.listService();
}
/** * 通过ID修改用户信息 * @param id * @param username * @param password * @return */
@PutMapping("/update/user/{id}")
public UserModel updateUserById(@PathVariable("id") Integer id,
@RequestParam("username") String username,
@RequestParam("password") String password) throws Exception{
return userServiceImpl.updateUserById(id, username, password);
}
/** * 通过ID删除用户信息 * @param id * @return */
@DeleteMapping("/del/user/{id}")
public boolean delUserById(@PathVariable("id") Integer id) throws Exception {
return userServiceImpl.delUserByIdService(id);
}
}
通过curl 或者 postman 依次执行以下API (parameters can’t be not null)
localhost:8080/create - POST
localhost:8080/get/user/id - GET
localhost:8080/user/list - GET
localhost:8080/update/user/id - PUT
localhost:8080/del/user/id - DELETE