content: package com.example.demo.service;
  
  import com.example.demo.domain.Department;
  import java.util.List;
  import java.util.Optional;
  
  /**
   * Service Interface for managing {@link Department}.
   */
  public interface DepartmentService {
      /**
       * Save a department.
       *
       * @param department the entity to save.
       * @return the persisted entity.
       */
      Department save(Department department);
  
      /**
       * Partially updates a department.
       *
       * @param department the entity to update partially.
       * @return the persisted entity.
       */
      Optional<Department> partialUpdate(Department department);
  
      /**
       * Get all the departments.
       *
       * @return the list of entities.
       */
      List<Department> findAll();
  
      /**
       * Get the "id" department.
       *
       * @param id the id of the entity.
       * @return the entity.
       */
      Optional<Department> findOne(Long id);
  
      /**
       * Delete the "id" department.
       *
       * @param id the id of the entity.
       */
      void delete(Long id);
  }
  