两人团队项目-石家庄地铁查询系统（web版）

　　大二上学期做过只有两号线的地铁查询系统，但是只能在控制台操作。这一次将线路加到了六条，并且要求web实现，下面简述一下设计思路和具体代码实现：

　　1.数据库建表

　　于我自己习惯而言，我写javaweb项目第一件事就是建库建表。六条线路，我选择了分六个表存储，这样的话实际操作起来，分离的每一条线会使dao层写函数方便很多。

　　每一个表中只有三列属性：id，name，nearline

建表完成后，就需要在dbutil中写数据库连接的代码，这部分代码是模板代码，只需要修改库名即可。

package dbutil;

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

public class DButil {
	public static String url = "jdbc:mysql://localhost:3306/subway?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8";
	public static String user = "root";
	public static String password = "";
	public static String driver = "com.mysql.cj.jdbc.Driver";
	public static Connection getConn() {
		Connection conn = null;
		try {
			Class.forName(driver);

		     // 连续数据库
            conn = DriverManager.getConnection(url, user, password);

		} catch (Exception e) {
			e.printStackTrace();
		}
		return 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();
			}
		}
	}
}　

下一步我选择写Javabean,因为每个表只有三个属性，所以javabean也十分简单，只有三个属性，只需要写他们的get和set方法，以及有参数和无参数的构造函数即可。

package bean;

public class Bean {
	private String name;
	private int number;
	private String nearline;

	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getNumber() {
		return number;
	}
	public void setNumber(int number) {
		this.number = number;
	}
	public String getNearline() {
		return nearline;
	}
	public void setNearline(String nearline) {
		this.nearline = nearline;
	}

	public Bean() {};
	public Bean(String name,int number,String nearline)
	{
		this.name=name;
		this.number=number;
		this.nearline=nearline;
	}

}

　　到这里我们的前期准备工作就已经做完了，现在还剩下dao包，servlet和前端界面以及输出界面没有书写，因为是两人团队项目，队友擅长前端，于是前端界面就交给他了。

　　在他写前端的同时，我自己大概写了dao包中的几个常用函数，如果以后还有需求，再往上添加。select函数必备，还有一个检测输入的站点在几号线的函数checkstation（），还有一个带参数的select函数，方便通过参数调用select每条线的功能，简化代码量。除此之外，最重要的函数就是在一条线上给定两个参数，将他们之间站名全部输出的函数substation。

　　

package dao;

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

import bean.Bean;
import dbutil.DButil;

public class Dao {

	public String[] substation(Bean[] sub,String s1,String s2)
	{
		ArrayList<String> stationlist =new ArrayList<String>();
		int start=0;
		int end=0;
		int money;
		int i;
		for(i=0;i<sub.length;i++)
		{
			if(sub[i].getName().equals(s1))
			start=i;
		}//确定起始站
		for(i=0;i<sub.length;i++)
		{
			if(sub[i].getName().equals(s2))
			end=i;
		}//确定终点站

		if(start<end)
		{
		for(i=start;i<=end;i++)
		{
			stationlist.add(sub[i].getName());
		}//输出站点信息
		}
		else
		{
			for(i=start;i>=end;i--)
			{
				stationlist.add(sub[i].getName());
			}//输出站点信息
		}
		return stationlist.toArray(new String[stationlist.size()]);
	}

	public int checkstation(String start)
	{
		Dao dao=new Dao();
		int i;
		for(i=0;i<dao.selectno1().length;i++)
		{
			if(dao.selectno1()[i].getName().equals(start))
			{
				return 1;
			}
		}
		for(i=0;i<dao.selectno2().length;i++)
		{
			if(dao.selectno2()[i].getName().equals(start))
			{
				return 2;
			}

		}
		for(i=0;i<dao.selectno3().length;i++)
		{
			if(dao.selectno3()[i].getName().equals(start))
			{
				return 3;
			}
		}
		for(i=0;i<dao.selectno4().length;i++)
		{
			if(dao.selectno4()[i].getName().equals(start))
			{
				return 4;
			}
		}
		for(i=0;i<dao.selectno5().length;i++)
		{
			if(dao.selectno5()[i].getName().equals(start))
			{
				return 5;
			}
		}
		for(i=0;i<dao.selectno6().length;i++)
		{
			if(dao.selectno6()[i].getName().equals(start))
			{
				return 6;
			}
		}
		return 0;
	}

	public Bean[] select(int n)
	{
		Bean[] a=new Bean[] {};
		Dao dao=new Dao();
		if(n==1)
			return dao.selectno1();
		if(n==2)
			return dao.selectno2();
		if(n==3)
			return dao.selectno3();
		if(n==4)
			return dao.selectno4();
		if(n==5)
			return dao.selectno5();
		if(n==6)
			return dao.selectno6();
		else
			return a;
	}

	public Bean[] selectno1()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no1 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取一号线的所有信息

	public Bean[] selectno2()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no2 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	 Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取二号线的所有信息

	public Bean[] selectno3()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no3 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	 Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取三号线的全部信息

	public Bean[] selectno4()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no4 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	 Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取四号线的全部信息

	public Bean[] selectno5()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no5 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	 Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取五号线的全部信息

	public Bean[] selectno6()
	{
		ArrayList<Bean> list=new ArrayList();
		Connection connection = DButil.getConn();
		Statement statement=null;
		ResultSet rs = null;
		try
		{
			statement = connection.createStatement();

		     // 要执行的SQL语句
		     String sql = "select * from no6 ";

		     // 结果集
		     rs = statement.executeQuery(sql);

		     while(rs.next())
		     {
		    	 Bean selectbean=new Bean();
		     String name = rs.getString("name");
		     int number = rs.getInt("id");
		     String nearline = rs.getString("nearline");

		 	selectbean.setName(name);
		 	selectbean.setNumber(number);
		    selectbean.setNearline(nearline);
		     list.add(selectbean);
		     }
		} catch (Exception e)
		{
			e.printStackTrace();
		} finally
		{
			DButil.close(rs, statement, connection);
		}
		return list.toArray(new Bean[list.size()]);
	}//获取六号线的全部信息

}

　　与此同时，我的队友已经将界面做好，给了我接口，我很佩服队友的功力，因为这个界面不套模板做成这样，已经是很不错了。