Usage of JavaScript in ADF Faces Rich Client Applications: guidelines and best practices

Using JS into ADF application is often considered a controversial topic.

I this white paper of ADF Design Fundamentals series, Franck Nimphius provides a guideline about how to properly use JS into an ADF application:

http://www.oracle.com/technetwork/developer-tools/jdev/1-2011-javascript-302460.pdf

The bottom line is:

If JavaScript is used, developers are encouraged to only use public ADF Faces client framework APIs instead of direct browser DOM manipulation and to stay away from using ADF Faces JavaScript objects stored in internal package hierarchies. 

This list of 10 best practices is extracted from the white paper above:

• Best Practice 1: An oven alone doesn’t make a cook. Developers should ensure they understand the ADF Faces client architecture before using JavaScript in ADF Faces applications. 
• Best Practice 2: Protected, package, or private methods and variables that DOM inspection tools like Firebug show for ADF Faces components and events should not be used in custom ADF Faces application development. 
• Best Practice 3: Application developers should ensure that a component exists on the client before accessing it from JavaScript. ADF Faces client component objects are created by setting the component clientComponent property to true or adding an af:clientListener tag. 
• Best Practice 4: Developers should not hardcode any client component id that shows in the generated HTML output for a page into their JavaScript functions. Client id values may change even between runs of a view. Instead developers can dynamically determine the client Id by a call to the ADF Faces component's getClientId method in a managed bean. 
• Best Practice 5: Application developers should call cancel()on all events that don't need to propagate to the server. 
• Best Practice 6: Client-to-server calls should be used sensibly to reduce the amount of network roundtrips and thus to prevent slow performance due to network latency. 
• Best Practice 7: No knowledge about framework internal implementation details should be used directly in JavaScript code. Instead, public APIs and constants should always be used. 
• Best Practice 8: JavaScript exceptions should be handled gracefully and not just suppressed. 
• Best Practice 9: The framework default behavior should be respected. The rich client component architecture and its APIs are performance optimized. Component functionality therefore should not be changed by call to the client component prototype handler. 
• Best Practice 10: JavaScript should not be used for implementing application security.