java jdbc使用SSH隧道连接mysql数据库demo

原文地址： https://blog.csdn.net/earbao/article/details/50216999，session.setPortForwardingL稍有改动

import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;

import java.sql.*;

//http://my.oschina.net/Thinkeryjgfn/blog/177283
//http://www.cnblogs.com/I-will-be-different/p/3925351.html?utm_source=tuicool&utm_medium=referral
//java jdbc使用SSH隧道连接mysql数据库demo
public class ChangeDB {



    public static void go() {
        try {
            JSch jsch = new JSch();
            Session session = jsch.getSession("yunshouhu", "192.168.0.102", 22);
            session.setPassword("xxxx");
            session.setConfig("StrictHostKeyChecking", "no");
            session.connect();
            System.out.println(session.getServerVersion());//这里打印SSH服务器版本信息

            //ssh -L 192.168.0.102:5555:192.168.0.101:3306 [email protected]  正向代理
           int assinged_port = session.setPortForwardingL((3306, mysqlurl, 3306);//端口映射 转发  数据库服务器地址url

           System.out.println("localhost:" + assinged_port);

            //ssh -R 192.168.0.102:5555:192.168.0.101:3306 [email protected]
            //session.setPortForwardingR("192.168.0.102",5555, "192.168.0.101", 3306);
           // System.out.println("localhost:  -> ");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }



    public static void main(String[] args) {


        try {
            //1、加载驱动
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        //2、创建连接
        Connection conn = null;
        Connection conn2 = null;
        try {

            conn2 = DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "hadoop", "xxxx");
            getData(conn2);
        } catch (SQLException e) {
            System.out.println("未连接上数据库");
            e.printStackTrace();
        }

        try{
            System.out.println("=============");
            go();
            conn = DriverManager.getConnection("jdbc:mysql://192.168.0.101:5555/mysql", "hadoop", "xxx");
            getData(conn);


        } catch (SQLException e) {
            e.printStackTrace();
        }



    }

    private static void getData(Connection conn) throws SQLException {

        // 获取所有表名
        Statement statement = conn.createStatement();
        ResultSet resultSet = statement
                .executeQuery("select * from help_keyword");
        // 获取列名
        ResultSetMetaData metaData = resultSet.getMetaData();
        for (int i = 0; i < metaData.getColumnCount(); i++) {
            // resultSet数据下标从1开始
            String columnName = metaData.getColumnName(i + 1);
            int type = metaData.getColumnType(i + 1);
            if (Types.INTEGER == type) {
                // int
            } else if (Types.VARCHAR == type) {
                // String
            }
            System.out.print(columnName + "\t");
        }
        System.out.println();
        // 获取数据
        while (resultSet.next()) {
            for (int i = 0; i < metaData.getColumnCount(); i++) {
                // resultSet数据下标从1开始
                System.out.print(resultSet.getString(i + 1) + "\t");
            }
            System.out.println();

        }
        statement.close();
        conn.close();
    }

}