Dynamic generation of HTML based on an object type

Question

I'm new to JSF so sorry if my question is trivial.

I have to present a list of items of three different types: let's say books, software and courses with different metadata (attributes) and requiring different visual representation.

Each of these items inherits from an abstract Item class, so I've a list of Items.

I thought to declare an abstract method getHtml() in the Item class so that each subclass can implement it's own "renderer" . Then in the XHTML page I'll call the getHtml() method using EL. The question is: is this the correct way? I see some drawbacks:

1. model mixed with view
2. HTML generated by means of Java code (quite difficult to maintain).

Any suggestion is appreciated.

I don't know if this synthetic presentation is clear enough: in case, please ask for clarifications.

Thanks in advance.

Answer 1

1. Create a page for choosing between the three, say, a drop dow list.
2. For the view, create three files: book.xhtml, boftware.xhtml, and courses.xhtml.

3. Then create one managed bean.

   @ManagedBean
   public class BkSoCoSelector {
   private String myChoice = null;
   //add setter and getter. 
   //add no-arg constructor. 
   }
   

4. Create a method in the above class to make dynamic choice[see example].note: The choice below is based on #1 above, the drop down list.

   public String pageSelector(){ //if null, return nothing. //if this.myChoice == book, return book; //no file extension needed. //do the same for the other files. }

5. On main page, #1, add the following

   <h:commandButton value = "Submit" action = "#{bkSoCoSelector.pageSelector()}"/>

To Summarise:

• Give the user a choice
• Set the chosen value to the instance variable. //done behind the scene.
• Get the now set instance variable.
• Base on the value of the instance variables, select a a page to display.