Method and apparatus for accessing data sources in a three tier environment

摘要

The present invention provides a three tier environment with improved data access capabilities. A browser can obtain data from a data source by interacting with that data source through an application server. The application server consists of a web server portion and a data server portion. Instead of CGI scripts interacting with a data source through a CGI interface, the present invention uses applets and objects to interact directly with a data source. A web page requested by a browser includes a "presentation" which is applet code that accesses data from a data source. When the application server receives a request for a page that is to contain data from a data source, the application server identifies a page that includes a reference to a presentation. The non-data portion of the page emits itself to the browser while at the same time the presentation undertakes the data retrieval. The browser receives the page, which contains an applet tag. The applet class is sent to the browser. The applet requests a URL that represents the data that is being retrieved for the page. The data is downloaded to the applet from the application server and displayed in the previously forwarded page. The presentation in the page working in conjunction with the data source takes the place of CGI scripting.