null check in jsf expression language
Please see this Expression Language
styleClass="#{obj.validationErrorMap eq null ? ' ' :
obj.validationErrorMap.contains('key')?'highlight_field':'highlight_row'}"
Even if the map is null, highlight_row
style is getting applied.
So I changed to
styleClass="#{empty obj.validationErrorMap ? ' ' :
obj.validationEr开发者_运维技巧rorMap.contains('key')?'highlight_field':'highlight_row'}"
Even then, highlight_row
is getting applied.
empty OR null
I dont want any style to be applied.
Any help? and reasons for this behaviour?
Use empty
(it checks both nullness and emptiness) and group the nested ternary expression by parentheses (EL is in certain implementations/versions namely somewhat problematic with nested ternary expressions). Thus, so:
styleClass="#{empty obj.validationErrorMap ? ' ' :
(obj.validationErrorMap.contains('key') ? 'highlight_field' : 'highlight_row')}"
If still in vain (I would then check JBoss EL configs), use the "normal" EL approach:
styleClass="#{empty obj.validationErrorMap ? ' ' :
(obj.validationErrorMap['key'] ne null ? 'highlight_field' : 'highlight_row')}"
Update: as per the comments, the Map
turns out to actually be a List
(please work on your naming conventions). To check if a List
contains an item the "normal" EL way, use JSTL fn:contains
(although not explicitly documented, it works for List
as well).
styleClass="#{empty obj.validationErrorMap ? ' ' :
(fn:contains(obj.validationErrorMap, 'key') ? 'highlight_field' : 'highlight_row')}"
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