Another documentation problem for [b]<f:selectItems>[/b]:
https://javaserverfaces.dev.java.net/nonav/docs/2.0/pdldocs/facelets/f/selectItems.html
It states that the [b]itemValue[/b] attribute should "evaluate to a Collection, array, or Map from which the items to be shown will be rendered". This is not true. Even the sample code on that same page clearly shows that [b]itemValue[/b] can be a plain object, even a String or an numeric.
As for the "one-time executed code", the original poster explained in his post what he means -- the validation of the registration should be performed only once. Any subsequent postbacks to that page should not perform the validation again.
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