public class TestThreads {
    public static class Thread1 implements Runnable {
        @Override
        public void run() {
            try {
                Connection connection = DriverManager
                        .getConnection("jdbc:mysql://localhost/test?"
                                + "user=myuser&password=mypassword");

                Statement statment = connection.createStatement();

                statment.executeQuery("select * from `table1`");

                [...]

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

    public static class Thread2 implements Runnable {
        @Override
        public void run() {
            try {
                Connection connection = DriverManager
                        .getConnection("jdbc:mysql://localhost/test?"
                                + "user=myuser&password=mypassword");

                Statement statment = connection.createStatement();

                statment.executeQuery("select * from `table2`");

                [...]

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

    public static void main(String[] args) {
        Thread thread1 = new Thread(new Thread1());
        Thread thread2 = new Thread(new Thread2());

        thread1.start();
        thread2.start();

        try {
            thread1.join(1000000);
            thread2.join(1000000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}