Obtain length of string in EL

Question

Can we find the length of a String in Facelets page to check for a condition using <ui:fragment>?

Answer 1

If you just need to know if it's empty or null, use EL empty keyword:

<ui:fragment rendered="#{not empty bean.string}">

Or if you really need to know its exact length, use String#length() method directly:

<ui:fragment rendered="#{bean.string.length() gt 42}">

Or if you aren't on Servlet 3.0 / EL 2.2 yet, use JSTL fn:length() function:

<ui:fragment rendered="#{fn:length(bean.string) gt 42}">