摘要：實體類編號姓名年齡和略層編寫用戶數據新增用戶數據修改用戶數據刪除根據用戶名稱查詢用戶信息根據用戶查詢用戶信息根據用戶查詢用戶信息業務層新增用戶修改用戶刪除用戶根據用戶名字查詢用戶信息根據用戶查詢用戶信息根據用戶查詢用戶信息實現層層編寫開始新

1 實體類

public class User {
     /** 編號 */
     private int id;
     /** 姓名 */
     private String name; 
     /** 年齡 */
     private int age;
     
     public User(){
     }
//   getter和 setter 略 
}

2 DAO層編寫

@Mapper
public interface UserDao {
    
    /**
     * 用戶數據新增
     */
     @Insert("insert into t_user(id,name,age) values (#{id},#{name},#{age})")
      void addUser(User user); 
     
     /**
      * 用戶數據修改
      */
     @Update("update t_user set name=#{name},age=#{age} where id=#{id}")
      void updateUser(User user);

     /**
      * 用戶數據刪除
     */
     @Delete("delete from t_user where id=#{id}")
     void deleteUser(int id);
    
      /**
     * 根據用戶名稱查詢用戶信息
     *
     */
    @Select("SELECT id,name,age FROM t_user where name=#{userName}")
    User findByName(@Param("userName") String userName);
   
    /**
     * 根據用戶ID查詢用戶信息
     *
     */
    @Select("SELECT id,name,age FROM t_user where id=#{userId}")     
    User findById(@Param("userId") int userId);
    
    
    /**
     * 根據用戶age查詢用戶信息
     */
    @Select("SELECT id,name,age FROM t_user where age = #{userAge}")     
    User findByAge(@Param("userAge") int userAge);
     
}

3 service業務層

public interface UserService {
    
    /**
     * 新增用戶
     * @param user
     * @return
     */
    boolean addUser(User user);
    
    /**
     * 修改用戶
     * @param user
     * @return
     */
    boolean updateUser(User user);
    
    
    /**
     * 刪除用戶
     * @param id
     * @return
     */
    boolean deleteUser(int id);
    
     /**
     * 根據用戶名字查詢用戶信息
     * @param userName
     */
    User findUserByName(String userName);
    
    /**
     * 根據用戶ID查詢用戶信息
     * @param userId
     */
    User findUserById(int userId);
    
     /**
     * 根據用戶ID查詢用戶信息
     * @param userAge
     */
    User findUserByAge(int userAge);
}

4 serviceImpl實現層

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDao userDao;
    
    
    @Override
    public boolean addUser(User user) {
        boolean flag=false;
        try{
            userDao.addUser(user);
            flag=true;
        }catch(Exception e){
            e.printStackTrace();
        }
        return flag;
    }

    @Override
    public boolean updateUser(User user) {
        boolean flag=false;
        try{
            userDao.updateUser(user);
            flag=true;
        }catch(Exception e){
            e.printStackTrace();
        }
        return flag;
    }

    @Override
    public boolean deleteUser(int id) {
        boolean flag=false;
        try{
            userDao.deleteUser(id);
            flag=true;
        }catch(Exception e){
            e.printStackTrace();
        }
        return flag;
    }

    @Override
    public User findUserByName(String userName) {
        return userDao.findByName(userName);
    }

    @Override
    public User findUserById(int userId) {
        return userDao.findById(userId);
    }

    @Override
    public User findUserByAge(int userAge) {
        return userDao.findByAge(userAge);
    }
}

4 controller層編寫

@RestController
@RequestMapping(value = "/api/user")
public class UserRestController {
    @Autowired
    private UserService userService;
 
    @RequestMapping(value = "/addUser", method = RequestMethod.POST)
    public boolean addUser( User user) {
        System.out.println("開始新增...");
        return userService.addUser(user);
    }
    
    @RequestMapping(value = "/updateUser", method = RequestMethod.PUT)
    public boolean updateUser( User user) {
        System.out.println("開始更新...");
        return userService.updateUser(user);
    }
    
    @RequestMapping(value = "/deleteUser", method = RequestMethod.DELETE)
    public boolean delete(@RequestParam(value = "userName", required = true) int userId) {
        System.out.println("開始刪除...");
        return userService.deleteUser(userId);
    }
    
    @RequestMapping(value = "/userName", method = RequestMethod.GET)
    public User findByUserName(@RequestParam(value = "userName", required = true) String userName) {
        System.out.println("開始查詢...");
        return userService.findUserByName(userName);
    }
    
    @RequestMapping(value = "/userId", method = RequestMethod.GET)
    public User findByUserId(@RequestParam(value = "userId", required = true) int userId) {
        System.out.println("開始查詢...");
        return userService.findUserById(userId);
    }
    
    @RequestMapping(value = "/userAge", method = RequestMethod.GET)
    public User findByUserAge(@RequestParam(value = "userAge", required = true) int userAge) {
        System.out.println("開始查詢...");
        return userService.findUserByAge(userAge);
    }
}