Form hold data which is submitted to trigger the action on server. In the conventional approach when form is submitted the posted data is retrieved at server side component by getting parameters, like
This requires a lot of plumbing code. to make it easier latest frameworks have come with a new concept called as “Binding”.
In Form binding you create an object(POJO) which is binded to the form. so whenever the form is submitted, the object gets populated automatically without writing any plumbing code.
Similarly the “Event Binding” happens. You can bind an event with the form, register a listener to it and when that particular even is fired, it invokes your action. A very beautiful implementation is implemented in GWT google web toolkit for the same.
The data can be bind to form with events like refresh, buffering etc using the xml configurations or annotations.
Sample from a Binding File
To give you an idea of what a binding file looks like, below a very simple example is shown.
<fb:context xmlns:fb="http://apache.org/cocoon/forms/1.0#binding" path="/" > <fb:value id="firstname" path="firstName"/> <fb:value id="lastname" path="lastName"/> <fb:value id="email" path="email"/> </fb:context>
With the dyna form in frame works like Struts 2.0 even the data object is created automatically via the xml configurations only. Hence it save time to write and maintain the data object class as well.