How to restrict the number of error messages appearing in af:messages

Question

Hii all....
Ihave customized the error messages which are produced when a constraint in a database are voilated using the following links
http://download-west.oracle.com/docs/cd/B32110_01/web.1013/b25947/web_val.htm#CIHJBIDJ
and by overriding the ListResourceBundle using the following link:http://one-size-doesnt-fit-all.blogspot.com/2007/05/dont-constrain-yourself-displaying.html
Now my problem is say, when a primary key is voilated i get repeated error messages and some unwanted error messages like 2,4(which are again repeated) as show below:
1.Empno - Employee Already Exists!!!
2.Empno - Attribute Empno in AppModule.EmpVO1 is required
3.Empno - Employee Already Exists!!!
4.Empno - Attribute Empno in AppModule.EmpVO1 is required
Now, i want the user to only see error numbered 1 and rest 2,3,4 should not be displayed on the screen ......plzzz knidly help me.

Answer 1

Hi,
In your ErrorHandler, override the method getDisplayMessage and in it add whatever message you'd like. Something like this:
    @Override
    public String getDisplayMessage(BindingContext bindingContext, Exception exception) {
        FacesContext fctx = FacesContext.getCurrentInstance();
        Iterator<FacesMessage> iterator = fctx.getMessages();
        if (exception instanceof JboException) {
            // do something (or nothing)
        } else if (exception instanceof UniqueNameException) {
            // add some message
            if (!iterator.hasNext()) fctx.addMessage(null, new FacesMessage(FacesMessage.SEVERITY_ERROR, "", "This is an UniqueNameException!");
        return null;
{code}
You can also try add some code to manipulate the iterator and remove all the messages, and then add only the one you want the user to see.
Pedja