Is it possible to use EL conditional operator in action attribute?

djmj picture djmj · May 6, 2012 · Viewed 23.3k times · Source

The conditional operator works in many attributes like "rendered" "value" and others.

But it does not work in action? Or am I doing it wrong?

<h:commandLink action="#{true ? bean.methodTrue() : bean.methodFalse()}"/>

Error: javax.el.ELException: Not a Valid Method Expression

(I realized it using primefaces ajax action attribute)

Answer

BalusC picture BalusC · May 28, 2012

This is not supported. The action attribute is supposed to be a MethodExpression, but the conditional operator makes it a ValueExpression syntax. I don't think this will ever be supported for MethodExpressions in EL.

You have basically 2 options:

  1. Create a single action method which delegates the job.

    <h:commandButton ... action="#{bean.method}" />
    

    with

    public String method() {
        return condition ? methodTrue() : methodFalse();
    }
    

    If necessary, pass it in as method argument by #{bean.method(condition)}.

  2. Or, conditionally render 2 buttons.

    <h:commandButton ... action="#{bean.methodTrue}" rendered="#{bean.condition}" />
    <h:commandButton ... action="#{bean.methodFalse}" rendered="#{not bean.conditon}" />