地铁系统初步思路

设计思路：首先在jsp中录入起始站和终点站，传值进入servlet，通过servlet中的方法调用dao层方法，去查询数据库中两个站点是否在一条线上，接受返回值，返回值为一个对象，通过对象调取方法，检测两个站点的number是否相同，相同则为同一条线，如不相同，则需换乘，目前只做到了一条线的，换乘的还在进行中，还未写完方法，一条线的需在调用一个方法，通过id将中间地站点输出，存在一个对象中，然后在另一个jsp中通过循环读取出来，一条线的可以成功运行，需换成的还在开发中

合作人：信1705-2  张利杰

代码：

package Dao;

import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;


import com.mysql.jdbc.Util;

import Entity.User;


import DB.DB;
import java.sql.*;




public class Dao {

    
    static String sql = "select * from first";
    private static final Statement DBUtil = null;
    public User search(String sname) {
        
        User user = new User();
        String sql = "select * from first where name='" + sname + "'";
        

        Connection conn = DB.getConn();
        Statement state = null;
        ResultSet rs = null;
        String number = null;
        try {
            state = conn.createStatement();
            rs = state.executeQuery(sql);
            while (rs.next()) {

                number = rs.getString("number");
                int id = rs.getInt("id");
                String name = rs.getString("name");
                String beizhu = rs.getString("beizhu");
                user = new User(id , number,  name,beizhu);
                

            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            DB.close(rs, state, conn);
        }

        return user;
    }
    
    
    
    
    public List<User> Load(User user1 , User user2) {
        int a= user1.getId();
        int b=user2.getId();
        if(user1.getNumber().equals(user2.getNumber())) {
        
    
    Connection conn = DB.getConn();
    String sql="select * from first where id between "+ a +" and "+ b +" ";
    Statement state = null;
    ResultSet rs = null;
    
    List<User> users = new ArrayList<User>();
    User user = null;
    try {
        state = conn.createStatement();
        rs = state.executeQuery(sql);
        while(rs.next()) {
            user = new User();
            user.setId(rs.getInt("id"));
            user.setNumber(rs.getString("number"));
            user.setName(rs.getString("name"));
            user.setBeizhu(rs.getString("beizhu"));
            
            users.add(user);
            System.out.println(user);
        }
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }finally {
        DB.close(rs,state, conn);
        
    }
return  users;
}
        
    

    
        return null;
        
    
}

}
    
    

package DB;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DB {
    public static String db_url = "jdbc:mysql://localhost:3306/test";
    public static String db_user = "root";
    public static String db_pass = "15568958907lx";
    
    public static Connection getConn () {
        Connection conn = null;
        
        try {
            Class.forName("com.mysql.jdbc.Driver");//閸旂姾娴囨す鍗炲З
            conn = DriverManager.getConnection(db_url, db_user, db_pass);
        } catch (Exception e) {
            e.printStackTrace();
        }
        
        return conn;
    }
    
    /**
     * 閸忔娊妫存潻鐐村复
     * @param state
     * @param conn
     */
    public static void close (Statement state, Connection conn) {
        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    
    public static void close (ResultSet rs, Statement state, Connection conn) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        
        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) throws SQLException {
        Connection conn = getConn();
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        String sql ="select * from USER";
        pstmt = conn.prepareStatement(sql);
        rs = pstmt.executeQuery();
        if(rs.next()){
            System.out.println("缁岋拷");
        }else{
            System.out.println("娑撳秶鈹�");
        }
    }

}

package Entity;

public class subway {
private String name;
private String number;
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getNumber() {
    return number;
}
public void setNumber(String number) {
    this.number = number;
}
public subway(String name,String number) {
    this.name = name;
    this.number = number;
}
}

package Entity;

public class User {
    private int id;
    private String number;
    private String name;
    private String beizhu;
    
    public User() {
        
    }
    

    public int getId() {
        return id;
    }


    public void setId(int id) {
        this.id = id;
    }


    public String getNumber() {
        return number;
    }


    public void setNumber(String number) {
        this.number = number;
    }


    public String getName() {
        return name;
    }


    public void setName(String name) {
        this.name = name;
    }


    public String getBeizhu() {
        return beizhu;
    }


    public void setBeizhu(String beizhu) {
        this.beizhu = beizhu;
    }


    public User(int id,String number,String name,String beizhu) {
        this.id=id;
        this.number = number;
        this.name = name;
    
        this.beizhu = beizhu;
        
    }

}

package Servlet;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import Dao.Dao;
import Entity.User;

/**
 * Servlet implementation class Servlet
 */
@WebServlet("/Servlet")
public class Servlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public Servlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // TODO Auto-generated method stub
        //response.getWriter().append("Served at: ").append(request.getContextPath());
        req.setCharacterEncoding("UTF-8");
        Dao dao = new Dao();
        
        String sname = req.getParameter("sname");
        String ename = req.getParameter("ename");
        
        User user1 = dao.search(sname);
        User user2 = dao.search(ename);
        
        if(user1.getNumber().equals(user2.getNumber())) {
        System.out.println(user1.getNumber());
        System.out.println(user2.getNumber());
            List<User> users = new ArrayList<User>();
//            User user=new User();
            

            users=dao.Load(user1,user2);
            req.setAttribute("users", users);
            req.getRequestDispatcher("login.jsp").forward(req,resp);
        }
        else if (!(user1.getNumber().equals(user2.getNumber()))) {
            System.out.println(user1.getNumber());
            System.out.println(user2.getNumber());
            
            List<User> users = new ArrayList<User>();
//            User user=new User();
            

            users=dao.Load(user1,user2);
            req.setAttribute("users", users);
            req.getRequestDispatcher("login.jsp").forward(req,resp);
        }
        
    }

    

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>石家庄地铁信息查询系统</title>
</head>
<body>
<%
         Object message = request.getAttribute("message");//放置一个字符串，并取出
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
    
    
        <form action="Servlet" method="post" onsubmit="return check()">
            <div class="a">
                <p style="text-align:center">始发站<input type="text" size="20" id="sname" name="sname"/></p>
            </div>
            <div class="a">
                <p style="text-align:center">终点站<input type="text" size="20" id="ename" name="ename" /></p>
            </div>
            
            <div class="a">
                <button type="submit" class="b">查&nbsp;&nbsp;&nbsp;询</button>
            </div>
            </form>
        
    </div>
    <script type="text/javascript">
        function check() {
            var username = document.getElementById("sname");;
            var password = document.getElementById("ename");
            //非空
            if(username.value == '') {
                alert('始发站不能为空');
                same.focus();
                return false;
            }
            if(password.value == '') {
                alert('终点站不能为空');
                ename.focus();
                return false;
            }
            
        }
    </script>
    
</body>
</html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
 <%@page import="Dao.Dao" %>
    <%@page import="Entity.User" %>
    <%@page import="java.util.List" %>
    <%@page import="java.util.ArrayList" %>
    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>显示全部信息</title>
</head>

<body>
    <table>
        <tr>
            <td>站台</td>
            <td>线路</td>
            
        
        </tr>
        <tr>
        <c:forEach items="${users}" var="item">
                <tr>
                    <td>${item.name}</td>                    
                    <td>${item.number}</td>
                </tr>
            </c:forEach>
            </table>
        </tr>
        
    </table>
**********************<br>
<input type="button" value="返回功能界面" onclick="window.location.href='index.jsp';"/><br>
**********************<br>
</body>
</html>
</body>
</html>

实验截图：

 实验总结：由于基础低，导致写起来非常困难，也借助了别人的力量，通过讲解理解了容器的用处，弥补了我之前只能接受一个变量的返回值，现在学会了接受对象的返回值，总体来说还是有进步，目前在写查询换乘站的算法，写完就可以实现换乘了。