Hi folks, I want to get your thoughts around using Castor in a web environment. For those of you not yet familiar with AJAX it is the age old technique of remotely scripting calls back to the server from a web page with out the need to refresh the page. Read more here http://www.xoscript.org/
Today I am using XOscript an open source AJAX implementation to talk to my Castor classes on the server. I am using a main class that does the work for my application and applies the data to my Castor class instance and then takes care of any database interaction and returns something appropriate back to the web application where the process continues. In the next stage of development I have been thinking about how I can have more robust interaction with my Castor classes and I would like to get your thoughts on what makes the most sense to you. Today I can generate classes from my xsd using the org.exolab.castor.builder.SourceGenerator. I can interact with my castor class by returning it from a method call back to my web application. At this point in the browser I have a proxy instance of my Castor class which contains no data and all of it's methods are mapped to remote calls behind the scenes. If I call a method on one of my Castor classes I get another proxy object and the process goes on. Here is where I am at a cross road, if the proxy object I get back from my method call to the server is another concrete class life is good. If the return type of my method call is java.util.Vector which Castor uses for collections I can use org.xoscript.javascript.util.JSCollection and return all of the contents of the vector to my web application. Maps and Collectons are support by special JavaScript objects that do the same work as the java.util classes. If I then iterate over the buckets in that collection and call a method on the object in that bucket it will be a proxy class who's methods are mapped back to the server as remote calls. My point here is that I am growing my dependency on bandwidth consumption and some consideration to how much I might use based on the hierarchy of my Castor tags. What I can do is use org.xoscript.builder.JScriptGenerator to generate the JavaScript equivalent of my Castor classes. At page load I can import this hierarchy of JavaScript objects into the browser where they are ready to marshall into instances xml sent from the server representing my Castor classes complete with the data. The generator uses the JavaScript version of a vector to manage collection just like in my Castor classes so now when I iterate over a collection I am touching the data. One concern in this approach is that if other clients interacts with my Castor classes, I now have a dirty read and unmarshalling the data back into xml and sending it back to the server for processing could mean that my instance data is out of sync with my disconnected web application. If you want to see an example of a class that was generated with the org.xoscript.builder.JScriptGenerator you can download the source code from http://www.xoscript.org/opencms/opencms/download/ and look at the js files that are in org.xoscript.jsobject.*, with the exception of the class-object and exception-object the other js classes were generated using the generator. Any comments are appreciated. Discussion on this topic may not be appropriate for this forum so I will invite you to make your comments in the xoscript discussion forum at google groups. http://groups-beta.google.com/group/xoscript Thanks for letting me ramble Bryan LaPlante ------------------------------------------------- If you wish to unsubscribe from this list, please send an empty message to the following address: [EMAIL PROTECTED] -------------------------------------------------
