[Myfaces Wiki] Update of "Tree2" by Jan Dockx

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The following page has been changed by Jan Dockx:
http://wiki.apache.org/myfaces/Tree2

New page:
The '''Tree2''' component renders a tree representation of your data with a HTML table. The tree is dynamic: nodes are expanded or collapsed when the user clicks them. The component supports both client side interaction through JavaScript, and server side interaction. In the latter case, each user click results in a request/response cycle, which re-renders the tree in the new view state.

Note that in the latter case only the visible (expanded) data is sent to the client. In the first case (client side tree), the entire tree is sent to the browser with every HTML response. Each node of the tree carries a sizable amount of HTML code with it (think 200 characters on average, depending on the amount of information you want to show in for a node), and this information is sent to the browser also for nodes that are not visible to the end user when the page is rendered, because one of their ancestor nodes is collapsed. If you have a tree, e.g., 4 levels deep, with 10 children on average for each node, you will transmit 10 + 10^2 + 10^3 + 10^4 = 11 110 nodes of 200 characters, or 2 222 000 characters, or roughly 2MB of data. This example should make clear that, although the client side tree gives a very good user experience, you could grow a bandwith problem very rapidly, so be aware. This tree is fit for small trees, or medium sized trees on an intranet or over a br
 oadband connection. For large trees, or when you need to take into account low-bandwidth connections, you should use the server side tree.