Return to Answer

###See also:

See also:

• When to use <ui:include>, tag files, composite components and/or custom components?

• When to use <ui:include>, tag files, composite components and/or custom components?

This is, unfortunately, "by design". The evaluation of the #{} expressions is deferred to the exact moment of the access-time. They're unlike "standard" EL ${} not evaluated at the exact moment they're been parsed by the tag handler and "cached" for future access during the same request/view. At the moment the <p:outputLabel> is rendered, and thus the #{cc.attrs.required} as referenced by UIInput#isRequired() needs to be evaluated, there's no means of any #{cc} in the EL context. So any of its attributes would not evaluate to anything. Only when you're sitting inside the <cc:implementation>, the #{cc} is available in the EL context and all of its attribues would thus successfully evaluate.

This is, unfortunately, "by design". The evaluation of the #{} expressions is deferred to the exact moment of the access-time. They're unlike "standard" EL ${} in JSP not evaluated at the exact moment they're been parsed by the tag handler and "cached" for future access during the same request/view. At the moment the <p:outputLabel> is rendered, and thus the #{cc.attrs.required} as referenced by UIInput#isRequired() needs to be evaluated, there's no means of any #{cc} in the EL context. So any of its attributes would not evaluate to anything. Only when you're sitting inside the <cc:implementation>, the #{cc} is available in the EL context and all of its attribues would thus successfully evaluate.