Spring Boot CRUD 操作，用于创建 Web 服务配置

问：

我是使用 Spring Boot 的新手。我正在尝试为 CRUD 操作创建一个 restful Web 服务。

我创建了模型、存储库和以下文件： 服务文件：

    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    @SpringBootApplication
    public class EmployeeServiceApplication {
     public static void main(String[] args) {
        SpringApplication.run(EmployeeServiceApplication.class, args);
     }
    }

控制器文件：

@RestController
public class Controller {

    @Autowired
    private EmployeeServiceDesc employeeService;

    @GetMapping("/employee/")
    public List<Employee> getAllEmployees() {
        return employeeService.getAllEmployees();
    }

    @GetMapping("/employee/{employeeId}")
    public Employee getEmployeeById(@PathVariable int employeeId) {
        return employeeService.getEmployeeById(employeeId);
    }

    @PostMapping("/employee/")
    public ResponseEntity<Void> add(@RequestBody Employee newEmployee, UriComponentsBuilder builder) {
        Employee employee = employeeService.addEmployee(newEmployee);
        if(employee == null) {
            return ResponseEntity.noContent().build();
        }
        HttpHeaders headers = new HttpHeaders();
        headers.setLocation(builder.path("/employee/{id}").buildAndExpand(employee.getId()).toUri());
        return new ResponseEntity<Void>(headers, HttpStatus.CREATED);
    }

    @PutMapping("/employee/")
    public ResponseEntity<Employee> updateEmployee(@RequestBody Employee v) {
        Employee employee = employeeService.getEmployeeById(v.getId());
        if(employee == null) {
            return new ResponseEntity<Employee>(HttpStatus.NOT_FOUND);
        }
        employee.setName(employee.getName());
        employee.setDOB(employee.getDOB());
        employee.setSalary(employee.getSalary());
        employeeService.updateEmployee(employee);
        return new ResponseEntity<Employee>(employee, HttpStatus.OK);
    }

    @DeleteMapping("/employee/{id}")
    public ResponseEntity<Employee> deleteEmployee(@PathVariable int id) {
        Employee employee = employeeService.getEmployeeById(id);
        if(employee == null) {
            return new ResponseEntity<Employee>(HttpStatus.FOUND);
        }
        employeeService.deleteEmployee(id);
        return new ResponseEntity<Employee>(HttpStatus.NO_CONTENT);
    }
}

当我通过Postman发送请求时，出现错误：未找到 我想我缺少一些配置，但不确定我应该做什么？谁能帮我解决这个问题？