Connection information.
This interface defines information needed for connection to database
(database and driver url, login name, password and schema name). It can create JDBC
connection and feels to be a bean (has propertychange support and customizer).
Instances of this class uses explorer option to store information about
open connection.
author: Slavek Psenicka, Radko Najman
Creates JDBC connection
Uses DriverManager to create connection to specified database. Throws
DDLException if none of driver/database/user/password is set or if
driver or database does not exist or is inaccessible.