Sun Java System Communications Express 6 2005Q4 Customization Guide

Understanding the File Layout in Mail

In mail, the static files are HTML and JavaScript files. These files have .html and .js extensions. These files are transmitted to the browser and used to retrieve dynamic contents from the server using a proprietary HTTP protocol. The mail server provides user interfaces for the stand-alone Messenger Express and the integrated mail component of Communication Express. The JavaScript files are shared by both these interfaces, and in general provide functionalities for the application.

Files that end with _fs_lr.html are used exclusively in the integrated mail component of the Communication Express. This section provides a basic overview on the various files used in the integrated mail component of Communication Express.

The CSS files that are used in mail are:

Table 4–1 shows the different JavaScript files that are used in Mail.

Table 4–1 JavaScript files that are used in Mail

JavaScript file Name  



Detects the browser to select which .css file should be used


Maintains the common UI codes shared by messaging listing and Search message result listing 


Checks for Domain security 


Maintains the Initialization and globally shared functions 


Utility functions 

add dtree.js

UI Codes for folder tree 

The frame work related files are,

The Mail page is configured to display the Mail page. It creates a number of frames, including several invisible frames. These invisible frames are used to pull the dynamic contents as JavaScript objects from the server. Once downloaded, the hidden frame can invoke the specific callback function in frameset HTML (_fs_lr.html) to render the updated dynamic contents.

The Mail component can be perceived as a dynamic client-side HTML engine. There are not many standard HTML statements in _fs_lr.html files. It is the ListFrameHTML() function in _fs_lr.html files which is responsible for the HTML output. This action takes place when ListFrameHTML() accesses the JavaScript objects from the hidden frames such as cfgFrame, msgFrame, and mboxFrame to generate the dynamic HTML page.