能力提升-飞机起降系统案例

能力提升-飞机起降系统案例

image.png

1. 数据库设计
   1.1 根据要求，需要设计两个表（机场表和机场信息表）
   1.1.1 机场表

   
   
   

   airport表
   
   

   1.1.2机场信息表

   
   
   

   airplane表

2. 搭建开发环境
   2.1 导jar包

   
   
   

   jar包
   
   

   2.2 全局配置文件

3. 实体类

public class Airport {
    private int id;
    private String portName;
    private String cityName;
    /**setter and getter**/
}

public class Airplane {
    private int id;
    private String airNo;
    private int time;
    private double price;
    private Airport takePort;
    private Airport landPort;
    /**setter and getter**/
}

4. 工具类

public class MapperUtil {
    //factory实例化过程是一个非常耗费性能的过程
    //保证有且只有一个factory
    private static SqlSessionFactory factory;
    private static ThreadLocal tl = new ThreadLocal<>();
    static{
        try {
            InputStream is = Resources.getResourceAsStream("mybatis.xml");
            factory = new SqlSessionFactoryBuilder().build(is); 
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }
    /**
     * 获取SqlSession的方法
     */
    public static SqlSession getSession(){
        SqlSession session = tl.get();
        if(session==null){
            tl.set(factory.openSession());
        }
        return tl.get();
    }
    /**
     * 关闭SqlSession的方法
     */
    public static void closeSession(){
        SqlSession session = tl.get();
        if(session!=null){
            session.close();
        }
        tl.set(null);
    }
}

5. mapper

public interface AirportMapper {
    /**
     * 查询所有起飞机场
     * @return
     */
    public List selTakePort();

    public List selLandPort();
}
------



    
        select * from airport where id in(select takeid from airplane);
    
    
        select * from airport where id in(select landid from airplane);
    

public interface AirplaneMapper {
    List selByTakeIdLandId(@Param("takeid") int takeId,@Param("landid") int landId);
}
-----



    
        
        
        
        
        
        
        
        
        
        
        
        
        
        
    
    
        select a.*,p.id takeid,p.portname takeportname,p.cityname takecityname,
        t.id landid,t.portname landportname,t.cityname landcityname
        from airplane a 
        left join airport p on a.takeid = p.id 
        left join airport t on a.landid = t.id
        
            
                and takeid=#{takeid}
            
            
                and landid=#{landid}
            
        
       

6. service层

public interface AirTakeService {
    public List showTake();
}
-----
public class AirTakeServiceImpl implements AirTakeService{
    @Override
    public List showTake() {
        SqlSession session = MapperUtil.getSession();
        AirportMapper airportMapper = session.getMapper(AirportMapper.class);
        return airportMapper.selTakePort();
    }
}

public interface AirLandService {
    public List showLand();
}
-----
public class AirLandServiceImpl implements AirLandService{
    @Override
    public List showLand() {
        SqlSession session = MapperUtil.getSession();
        AirportMapper airportMapper = session.getMapper(AirportMapper.class);
        return airportMapper.selLandPort();
    }
}

public interface AirplaneService {
    List showAirplane(int takeId,int landId);
}
-----
public class AirplaneServiceImpl implements AirplaneService{
    @Override
    public List showAirplane(int takeId, int landId) {
        
         SqlSession session = MapperUtil.getSession();
         AirplaneMapper airplaneMapper = session.getMapper(AirplaneMapper.class);
         return airplaneMapper.selByTakeIdLandId(takeId, landId);
    }   
}

7. servlet层

@WebServlet("/showtake")
public class ShowTakeServlet extends HttpServlet{
    AirTakeService ats = new AirTakeServiceImpl();
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        List showTake = ats.showTake();
        req.setAttribute("showtake", showTake);
        req.getRequestDispatcher("/showland").forward(req, resp);
        return;
    }
}
-----
@WebServlet("/showland")
public class ShowLandServlet extends HttpServlet {
    AirLandService als = new AirLandServiceImpl();
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        List showLand = als.showLand();
        req.setAttribute("showland", showLand);
        req.getRequestDispatcher("/showAirplane").forward(req, resp);
        return;
    }
}
-----
@WebServlet("/showAirplane")
public class ShowAirplaneServlet extends HttpServlet{
    private AirplaneService as = new AirplaneServiceImpl();
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int takeId = 0;
        String takeIdStr = req.getParameter("takeid");
        if(takeIdStr!=null&&!takeIdStr.equals("")){
            takeId = Integer.parseInt(takeIdStr);
        }
        int landId = 0;
        String landIdStr = req.getParameter("landid");
        if(landIdStr!=null&&!landIdStr.equals("")){
            landId = Integer.parseInt(landIdStr);
        }
        req.setAttribute("airplane", as.showAirplane(takeId, landId));
        req.getRequestDispatcher("/index.jsp").forward(req, resp);
        return;
    }
}

8. filter

@WebFilter("/*")
public class OpenSessionInView implements Filter{
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        // TODO Auto-generated method stub  
    }
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        SqlSession session = MapperUtil.getSession();
        try{
            chain.doFilter(request, response);
            session.commit();
        }catch(Exception e){
            session.rollback();
            e.printStackTrace();
        }finally{
            MapperUtil.closeSession();
        }   
    }
    @Override
    public void destroy() {
        // TODO Auto-generated method stub  
    }
}

9. index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>








起飞机场:

    请选择
    
    ${take.portName}
    


    
降落机场:

    请选择
    
    ${land.portName}
    




    

    

        
飞机编号
        
起飞机场
        
起飞城市
        
降落机场
        
降落城市
        
航行时间
        
价格(元)
    
    

        
${plane.airNo}
        
${plane.takePort.portName}
        
${plane.takePort.cityName}
        
${plane.landPort.portName}
        
${plane.landPort.cityName}
        

            
                小时
            
            
                ${plane.time%60}分钟
            
        
        
${plane.price}