import java.sql.*;

public class Connectivity {
	static final String DRIVER = "com.mysql.jdbc.Driver";
	static final String DB_URL = "jdbc:mysql://localhost/demo";
	//database credentials
	static final String Uname = "root";
	static final String Pass = "#Tandy1997";
	public static void main(String[] args) {
		Connection conn = null;//connection object.

		//Register our driver
		try{
		 Class.forName("com.mysql.jdbc.Driver")	;
		System.out.println("connecting to database...");
		conn = DriverManager.getConnection(DB_URL,Uname,Pass);
	}catch(SQLException e){System.out.println("An error occured "+e.getErrorCode());}
		catch(Exception e){
			System.out.println(e.getMessage());
		}
		finally{
			//close Resources.
			try{
				if(conn!=null){
				conn.close();}
			}catch(SQLException e){
				System.out.println(e.getMessage());
			}
		}
}
}


Look at the Error log...

Error: Main method not found in class Connectivity, please define the main method as:
   public static void main(String[] args)
or a JavaFX application class must extend javafx.application.Application