RESTful API设计原则与实现示例详解

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

public class User {
    private Long id;
    private String name;
    private String email;
    // 构造函数、getter和setter方法
}

import org.springframework.http.httpstatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import java.util.ArrayList;
import java.util.List;
@RestController
@RequestMapping("/users")
public class UserController {
    private List<User> users = new ArrayList<>();
    @GetMapping
    public ResponseEntity<List<User>> getUsers() {
        return new ResponseEntity<>(users, HttpStatus.OK);
    }
    @GetMapping("/{id}")
    public ResponseEntity<User> getUser(@PathVariable Long id) {
        User user = users.stream()
                .filter(u -> u.getId().equals(id))
                .findFirst()
                .orElse(null);
        if (user == null) {
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }
        return new ResponseEntity<>(user, HttpStatus.OK);
    }
    @PostMapping
    public ResponseEntity<User> createUser(@RequestBody User newUser) {
        users.add(newUser);
        return new ResponseEntity<>(newUser, HttpStatus.CREATED);
    }
    @PutMapping("/{id}")
    public ResponseEntity<User> updateUser(@PathVariable Long id, @RequestBody User updatedUser) {
        User user = users.stream()
                .filter(u -> u.getId().equals(id))
                .findFirst()
                .orElse(null);
        if (user == null) {
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }
        user.setName(updatedUser.getName());
        user.setEmail(updatedUser.getEmail());
        return new ResponseEntity<>(user, HttpStatus.OK);
    }
    @DeleteMapping("/{id}")
    public ResponseEntity<Void> deleteUser(@PathVariable Long id) {
        User user = users.stream()
                .filter(u -> u.getId().equals(id))
                .findFirst()
                .orElse(null);
        if (user == null) {
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }
        users.remove(user);
        return new ResponseEntity<>(HttpStatus.NO_CONTENT);
    }
}