?? Figure out which JSF UIComponent caused a BackingBean "get" method call?

Question

Hi,
I have a little problem with using JSF UIComponents and Backing beans.
I have an JSF Input TextField and this textField points to a backing bean attribute "Data.value" (to store the input). Code:
<h:inputText styleClass="entryInput"
id="textNumberOfServersInput"
value="#{AllData.value}">
</h:inputText>
The Backing bean for that looks like this (just the really important stuff):
public class AllDataBean
String value = null;
public String getValue()
return value;
public void setValue(String string)
value = string;
Now my problem is that, when calling the "getValue()" method I want to know which UIComponent caused that getValue() method call. I would like to know that UIComponent's ID. In the above example (textField) this id would be "textNumberOfServersInput" . HOW CAN I GET THE requesting UIComponent 's ID ?
At the end my getValue method should look like this:
public String getValue()
String requestingUIComponentID = IWouldLikeToKnowThat();
return value;
Thanks

Answer 1

Ahh, that's interesting. But any component can do a get. In other
words, you can have several components that point to the same bean
property. Assuming your pages are fairly static in nature, you could
instrument them with JSTL c:set calls to manually stick an identifier
into the namespace. Something like this:
<h:form id="form">
<c:set var="doAGet" scope="request" value="button" />
<h:commandButton id="button" value="#{bean.label}" />
<c:remove var="doAGet" scope="request" />
<c:set var="doAGet" scope="request" value="text" />
<h:outputText id="text" value="#{bean.label2}" />
<c:remove var="doAGet" scope="request" />
</h:form>
Then, in your backing bean, you could do:
public String getLabel() {
FacesContext context = FacesContext.getCurrentInstance();
String id = (String)
context.getExternalContext().getRequestMap().get("button");
id = "form:" + id;
UIComponent component = context.getViewRoot().findComponent("id");
It's clunky but it works. I'll ask the EG if they think we should add
the ability for the get() to more easily discover the calling component,
if any.
Ed (EG Member)