Java框架如何创建用于Web应用程序的API？

// 导入 Spring Boot 相关依赖
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.*;
import java.util.List;

// 定义实体类
@Entity
class Student {
    @Id
    @GeneratedValue
    private Long id;
    private String name;
    private int age;
    // 省略 getters 和 setters
}

// 定义仓库接口
interface StudentRepository extends JpaRepository<Student, Long> {}

// 定义控制器
@RestController
@RequestMapping("/api/students")
class StudentController {

    @Autowired
    private StudentService studentService;

    // 创建学生
    @PostMapping
    public Student createStudent(@RequestBody Student student) {
        return studentService.createStudent(student);
    }

    // 获取所有学生
    @GetMapping
    public List<Student> getAllStudents() {
        return studentService.getAllStudents();
    }

    // 获取单个学生
    @GetMapping("/{id}")
    public Student getStudentById(@PathVariable Long id) {
        return studentService.getStudentById(id);
    }

    // 更新学生
    @PutMapping("/{id}")
    public Student updateStudent(@PathVariable Long id, @RequestBody Student student) {
        return studentService.updateStudent(id, student);
    }

    // 删除学生
    @DeleteMapping("/{id}")
    public void deleteStudent(@PathVariable Long id) {
        studentService.deleteStudent(id);
    }
}

// 主应用程序类
@SpringBootApplication
public class App {
    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}