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

import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import java.sql.Connection;


public class DatabaseTest {

/**
 * Java Program to connect to remote database through SSH using port forwarding
 * @author Pankaj@JournalDev
 * @throws SQLException
 */
public static void main(String[] args) throws SQLException {

    int lport=5656;
    String rhost="some.url.uk";
    String host="some.url.uk"; //
    int rport=3306;
    String user="REDACTED";
    String password="REDACTED";
    String dbuserName = "REDACTED";
    String dbpassword = "REDACTED";
    String url = "jdbc:mysql://localhost:"+lport+"/MYDB";
    String driverName="com.mysql.jdbc.Driver";
    Connection conn = null;
    Session session= null;
    try{
        //Set StrictHostKeyChecking property to no to avoid UnknownHostKey issue
        java.util.Properties config = new java.util.Properties();
        config.put("StrictHostKeyChecking", "no");
        JSch jsch = new JSch();
        session=jsch.getSession(user, host, 22);
        session.setPassword(password);
        session.setConfig(config);
        session.connect();
        System.out.println("Connected");
        int assinged_port=session.setPortForwardingL(lport, rhost, rport);
        System.out.println("localhost:"+assinged_port+" -> "+rhost+":"+rport);
        System.out.println("Port Forwarded");

        //mysql database connectivity
        Class.forName(driverName).newInstance();
        conn = DriverManager.getConnection (url, dbuserName, dbpassword);
        System.out.println ("Database connection established");
        System.out.println("DONE");
    }catch(Exception e){
        e.printStackTrace();
    }finally{
        if(conn != null && !conn.isClosed()){
            System.out.println("Closing Database Connection");
            conn.close();
        }
        if(session !=null && session.isConnected()){
            System.out.println("Closing SSH Connection");
            session.disconnect();
        }
    }
}

}

com.jcraft.jsch.JSchException: java.net.ConnectException: Connection refused (Connection refused)
    at com.jcraft.jsch.Util.createSocket(Util.java:349)
at com.jcraft.jsch.Session.connect(Session.java:215)
at com.jcraft.jsch.Session.connect(Session.java:183)
at DatabaseTest.main(DatabaseTest.java:40)
Caused by: java.net.ConnectException: Connection refused (Connection refused)
at java.net.PlainSocketImpl.socketConnect(Native Method)
at       java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at     java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at java.net.Socket.connect(Socket.java:538)
at java.net.Socket.<init>(Socket.java:434)
at java.net.Socket.<init>(Socket.java:211)
at com.jcraft.jsch.Util.createSocket(Util.java:343)
... 3 more