A DO file is a Java servlet file that is used by web servers for delivering web-based Java applications. It is commonly associated with the Struts controller of applications that processes files. This allows DO files generate dynamic webpages that contain visual appearance as well as data retrieved from databases. Java servlets sends these dynamically generated web application pages to requesting browser for display.
DO File Format
DO files are saved as web files that are opened in browser when a user sends a request to the server. The servlet processes the request and sends the DO file as servlet to requesting browser.