sjz地铁作业

合作人：杨瑞

实现的功能：基本实现功能，能在网页实现最少换乘的路线，还未实现最短路线的功能，页面不够美观，甚至可以说太难看；代码冗余，接下来需要优化。

时间花费：预计花费10个小时，实际花费7个小时；

实验心得：这次是真正尝到了写代码的乐趣，也体会到了算法的重要性，从头到尾感觉到了这个项目的实施过程。通过将一个大问题逐渐分成若干小问题，然后各个击破，再次体会到了分而治之的重要性。

实验算法：

package com.subway.Dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.subway.Model.Subway;
import com.subway.Util.DBUtil;

public class SubwayDao {
    
    
        
        public static Subway load(String zhan) {
                
              //获得链接对象
                Connection connection = DBUtil.getConnection();
                //准备sql语句
                String sql = "select * from t_subway where station like ?";
                
                
                //创建语句传输对象
                PreparedStatement preparedStatement = null;
                ResultSet resultSet = null;
                Subway subway=null;
                
                try {
                    preparedStatement = connection.prepareStatement(sql);
                    preparedStatement.setString(1, zhan);
                    resultSet = preparedStatement.executeQuery();
                    
                    while(resultSet.next()) {
                        subway=new Subway();
                        subway.setId(resultSet.getInt("id"));
                        subway.setLine(resultSet.getString("line"));
                        subway.setStation(zhan);
                        subway.setTransfer(resultSet.getString("transfer"));            
                    }
                    
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }finally {
                    DBUtil.close(resultSet);
                    DBUtil.close(preparedStatement);
                    DBUtil.close(connection);
                }
                return subway;
        }
        
        public static String [] load(int id1,int id2) {
            String []list=new String[200];
            int num=0;
            //获得链接对象
            Connection connection = DBUtil.getConnection();
            String sql=null;
            //准备sql语句
            if(id1<id2) {
               sql = "select * from t_subway  where id > ? &&id<= ?";
            }
            else {
                sql = "select * from t_subway  where id < ? &&id>= ? order by id desc";
            }
            
            //创建语句传输对象
            PreparedStatement preparedStatement = null;
            ResultSet resultSet = null;
            try {
                preparedStatement = connection.prepareStatement(sql);
                preparedStatement.setInt(1, id1);
                preparedStatement.setInt(2, id2);
                resultSet = preparedStatement.executeQuery();
                while(resultSet.next()) {
                    list[num]=resultSet.getString("station");
                    num++;
                }
//                for(int i=0;i<num;i++) {
//                    System.out.println(list[i]);
//                }
                
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally {
                DBUtil.close(resultSet);
                DBUtil.close(preparedStatement);
                DBUtil.close(connection);
            }
            return list;
                
        }
        public static String[] load(Subway subway1,Subway subway2) {
            String []list=new String[200];
            Subway subway=null;
            //获得链接对象
            Connection connection = DBUtil.getConnection();
            //准备sql语句
            String sql = "select * from t_subway  where  line like ? && transfer like ? ";
            
            //创建语句传输对象
            PreparedStatement preparedStatement = null;
            ResultSet resultSet = null;
            try {
                preparedStatement = connection.prepareStatement(sql);
                preparedStatement.setString(1,subway1.getLine());
                preparedStatement.setString(2,subway2.getLine());
                resultSet = preparedStatement.executeQuery();
              
                if(resultSet.next()) {
                    subway=new Subway();
                    subway.setId(resultSet.getInt("id"));
                    subway.setLine(resultSet.getString("line"));
                    subway.setStation(resultSet.getString("station"));
                    subway.setTransfer(resultSet.getString("transfer"));
                }
                list=load(subway1.getId(),subway.getId());
                int n=0;
                for(n=0;n<list.length;n++)
                {
                    if(list[n]==null)
                         break;
                    
                }
                list[n-1]=list[n-1]+"(换乘"+subway.getTransfer()+")";
                
                System.out.println("*********************"+n);
                
                sql = "select * from t_subway  where  station like ? && line != ? ";
                try {
                    preparedStatement = connection.prepareStatement(sql);
                    
                    preparedStatement.setString(1,subway.getStation());
                    preparedStatement.setString(2,subway.getLine());
                    resultSet = preparedStatement.executeQuery();                    
                        if(resultSet.next()) {
                            subway=new Subway();
                            subway.setId(resultSet.getInt("id"));
                            subway.setLine(resultSet.getString("line"));
                            subway.setStation(resultSet.getString("station"));
                            subway.setTransfer(resultSet.getString("transfer"));
                        }
                    
                    
                    String[]arr=load(subway.getId(),subway2.getId());
                                        
                        for(int j=0;j<arr.length;j++)
                            if(arr[j]!=null) {
                                list[n]=arr[j];
                                n++;
                            }
                    
                    
                } catch (Exception e) {
                    // TODO: handle exception
                }
                
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally {
                DBUtil.close(resultSet);
                DBUtil.close(preparedStatement);
                DBUtil.close(connection);
            }
            return list;
                
        }
        public  String[] load(String qidian,String zhongdian) {
                String []list=new String[200];
                Subway subway1=load(qidian);
                Subway subway2=load(zhongdian);
               
                
                System.out.println("起点站："+subway1.getId()+" "+subway1.getLine()+" "+subway1.getStation()+" "+subway1.getTransfer());
                System.out.println("终点站："+subway2.getId()+" "+subway2.getLine()+" "+subway2.getStation()+" "+subway2.getTransfer());
                
                if(subway1.getLine().equals(subway2.getLine())) 
                    list=load(subway1.getId(),subway2.getId()); 
                    
                else 
                    list=load(subway1,subway2);        
                return list;
        }
            
    }

实验截图：