3.26web和android端地铁查询开发学习总结-526互联

web端的思想在前面已经写了，Android端的思想

跟web端差不多少，其中不一样的就是连接MySQL

数据库，其要求的jar包是5版本左右的，而且还涉及

到线程的问题，在连接MySQL的时候要另外启动一个

线程进行连接，主要思想上没啥改变，就是每次每种

查询要加一个button并且对应Onclick事件，在这个事件

里面启动一个新的线程。

我的队友是江新兵，我俩在此次开发中收获了很多。

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

public class DBOpenHelper {
    private final static String driver = "com.mysql.jdbc.Driver";
    private final static String url = "jdbc:mysql://10.99.121.251/kebiao?useUnicode=true&characterEncoding=UTF-8&useSSL=false";//
    private final static String username = "root";
    private final static String password = "123456";

    Connection conn=null;
    Statement st=null;
    ResultSet rs=null;

    static {
        try {
            Class.forName(driver);
        } catch (ClassNotFoundException e) {
            System.out.println("加载驱动错误");
        }
    }

    //2. 获取连接
    public static Connection getConnect() throws Exception {
        return DriverManager.getConnection(url, username, password);
    }

    //3. 释放连接资源

    public static void release(Connection conn, Statement st, ResultSet rs) throws Exception {
        if (rs != null) {
            rs.close();
        }
        if (st != null) {
            st.close();
        }
        if (conn != null) {
            conn.close();
        }

    }
/*private static String diver = "com.mysql.jdbc.Driver";
    //加入utf-8是为了后面往表中输入中文，表中不会出现乱码的情况
    private static String url = "jdbc:mysql://10.99.117.52we?characterEncoding=utf-8";
    private static String user = "root";//用户名
    private static String password = "hzl02096";//密码
    *//*
     * 连接数据库
     * *//*
    public static Connection getConn(){
        Connection conn = null;
        try {
            Class.forName(diver);
            conn = (Connection) DriverManager.getConnection(url,user,password);//获取连接
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }*/

}

  public int findstationsatrole(String roles) throws Exception {
        Connection conn = null;
        Statement state = null;
        ResultSet find = null;
        int stationsnumber = 0;
        try {
            conn = DBOpenHelper.getConnect();
            state = conn.createStatement();
            roles = roles + "号线";
            String sql = "SELECT  sname FROM biejing_subway"
                    + " WHERE sline='" + roles + "';";
            find = state.executeQuery(sql);

            stationsnumber = -1;

            while (find.next()) {
                stationsnumber++;
                onrolestation[stationsnumber] = new String();
                onrolestation[stationsnumber] = find.getString(1);
            }
            if (stationsnumber != -1) {
                for (int i = 0; i <= (stationsnumber / 2) + 1; i++) {
                    stationss = stationss + onrolestation[i]+" , ";
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            DBOpenHelper.release(conn, state, find);
        }

        return stationsnumber;
    }

    public int findrolesatstation(String stations) throws Exception {
        Connection conn = null;
        Statement state = null;
        ResultSet find = null;
        int stationsnumber = 0;
        int rolesnumber = 0;
        try {
            conn = DBOpenHelper.getConnect();
            state = conn.createStatement();
            String sql = "SELECT  sline FROM biejing_subway"
                    + " WHERE sname='" + stations + "';";
            find = state.executeQuery(sql);

            rolesnumber = -1;
            int zhuanhuan = 0;
            while (find.next()) {
                if (zhuanhuan % 2 == 0) {
                    rolesnumber++;
                    onstationatroles[rolesnumber] = new String();
                    onstationatroles[rolesnumber] = find.getString(1);

                }
                System.out.print(rolesnumber);
                zhuanhuan++;
            }

            if(rolesnumber!=-1) {
                for (int i = 0; i <= rolesnumber; i++) {
                    rolessss = rolessss + onstationatroles[i] + " , ";
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            DBOpenHelper.release(conn, state, find);
        }

        return rolesnumber;
    }