本文大概500字,阅读大概需要5分钟
**
可以参考这篇文章,进行快速初始化springboot web。
在java文件夹下的com.example.demo创建entity文件夹,并且创建User类,写入:
package com.example.demo.entity;
public class User {
private Integer id;
private String username;
private String address;
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 getAddress() { return address; }
public void setAddress(String address) { this.address = address; }
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", address='" + address + '\'' +
'}';
}
public User(Integer id, String username, String address) {
this.id = id;
this.username = username;
this.address = address;
}
public User() {
}
}
我们先用map来映射查询关系,后续将改成MyBatis整合
在java文件夹下的com.example.demo创建service文件夹,并且创建UserService类,写入:
package com.example.demo.service;
import com.example.demo.entity.User;
import org.springframework.stereotype.Component;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Component
public class UserService {
private static Map<Integer, User> users = new HashMap<>();
static {
users.put(1, new User(1, "Jack", "Beijing"));
users.put(2, new User(2, "Mary", "Beijing"));
users.put(3, new User(3, "Jane", "Shanghai"));
users.put(4, new User(4, "Michael", "Shanghai"));
}
/**
* 根据id查询用户
* @param id
* @return
*/
public User getUserById(Integer id) {
return users.get(id);
}
/**
* 根据id查询所有用户
* @return
*/
public List<User> getAllUser() {
return new ArrayList(users.values());
}
/**
* 更新用户
* @param user
* @return
*/
public void update(User user) {
users.replace(user.getId(), user);
}
/**
* 新增用户
* @param user
* @return
*/
public void add(User user) {
Integer newId = users.size()+1;
user.setId(newId);
users.put(newId, user);
}
/**
* 删除用户
* @param user
* @return
*/
public void delete(Integer id) {
users.keySet().removeIf(key -> key == id);
}
}
在java文件夹下的com.example.demo创建controller文件夹,并且创建UserController类,写入:
package com.example.demo.controllers;
import com.example.demo.entity.Result;
import com.example.demo.entity.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping("/user")
public class UserController {
// Rest /user/1
@Autowired
UserService userService;
// 查询 /user/1
@GetMapping("/{id}")
public Result getUser(@PathVariable Integer id) {
System.out.println(id);
User user = userService.getUserById(id);
return new Result<>(200, "查询成功", user);
}
// 新增 /user/add
@PostMapping("/add")
public Result addUser(@RequestBody User user) {
userService.add(user);
return new Result<>(200, "添加成功");
}
// 修改 /user/1
@PutMapping("/{id}")
public Result editUser(@RequestBody User user) {
userService.update(user);
return new Result<>(200, "修改成功");
}
// 删除 /user/1
@DeleteMapping("/{id}")
public Result deleteUser(@PathVariable Integer id) {
userService.delete(id);
return new Result<>(200, "删除成功");
}
}
测试效果:

在学习springboot的路上,如果你觉得本文对你有所帮助的话,那就请关注点赞评论三连吧,谢谢,你的肯定是我写博的另一个支持。