Question

I am trying to add a dynamic onclick event using rich:findComponent as:

<font class="topFirstTablehdCategory2" style="font-size: 12px; cursor: pointer;" onclick="#{rich:findComponent('benchmarkEndDate').value = channelPerformanceController.resetDate}">
    RESET
</font>

But I am getting

com.sun.el.parser.ParseException: Encountered "=" at line 1, column 48.

What I am willing to do, is to set string value to a rich:calender whose id is benchmarkEndDate supplied from the field resetDate of ChannelPerformanceController class.

I also write a javascript method in the jsp page:

function setResetDate(id, date) {
    #{rich:findComponent('benchmarkEndDate').value} = date;
}

is not working. It is called as: onclick="setResetDate('benchmarkEndDate', '#{channelPerformanceController.resetDate}')"

It is rendering in browser as:

function setResetDate(id, date) {
        2011-03-24 00:00:00.0 = date;
}

This method:

function setResetDate(id, date) {
        document.getElementById(#{rich:clientId(id)}) = date;
}

is change into :

function setResetDate(id, date) {
        document.getElementById() = date;
}

What I am doing wrong? How can I achieve this?

Answer 1

• JavaScript is executed by the client.
• Expression Language expressions are evaluated on the server before the markup is sent to the browser.

---

#{foo = bar} is not a valid EL expression. = is not a valid operator in EL. EL does not have an assignment operator. The only way to assign values via EL is using a value binding in attributes that support them (almost exclusively via JSF input controls).

---

If this expression is evaluated:

#{rich:clientId(id)}

This expression will search the request, session and application scopes looking using getAttribute("id"), using managed bean mechanisms to create such a bean if it is defined with this id. When this is evaluated and returns null, nothing will be rendered.

---

If this expression is not evaluated:

#{rich:clientId(id)}

Then it is being placed in template text (probably in JSP 2.0/J2EE 1.4.)

There are two types of EL expression:

• #{foo} – deferred expression: only evaluated in attributes that allow them
• ${foo} – immediate expression: allowed in template text

Beginning with JSP 2.1, it is a translation error to have a deferred expression in template text. From the JSP 2.1 specification:

When used in template text in a JSP page, the #{ character sequence
triggers a translation error, unless specifically allowed through a
configuration setup. This is because the #{} syntax is associated
exclusively with deferred-evaluation in JSP
2.1 and does not make sense in the context of template text (only
immediate evaluation using the ${expr} syntax makes sense in
template text).

In a tag file, #{expr} in template text is handled according to the
tag file’s JSP version: If the tag file’s JSP version is 2.0 or less,
#{expr} in template text will not cause any error. If the tag file’s
JSP version is equal to or greater than 2.1, #{expr} in template
text must cause an error, unless it has been escaped or the tag file
contains a deferredSyntaxAllowedAsLiteral tag directive attribute
set to TRUE.

Generally, #{foo} expressions must be in JSF control attributes only (for JSP views).

---

If you want to change a server-side value, use a form submit and action binding. This can be done via AJAX in RichFaces.