Af:commandButton text EL expression evaluated twice

Question

hi
For a button like this ...
<af:commandButton text="#{backing_SomePage.myCButtonText}" id="myCButton"/>... that gets its text property value from a backing bean method like this ...
public class SomePage
     public String getMyCButtonText()
          System.out.println("SomePage.getMyCButtonText() : begin");
          return "myCButton text";
}... results in output like this ...
SomePage.getMyCButtonText() : begin
SomePage.getMyCButtonText() : beginSo, the backing bean method is called twice.
See also this example application,
at http://verveja.footsteps.be/~verveja/files/oracle/ButtonTextExpressionIssue-v0.02.zip
questions
Why is the EL expression for the text property of a af:commandButton evaluated twice?
Is there a way to avoid this behaviour and have the the backing bean method called only once?
many thanks
Jan Vervecken

Answer 1

Hmm,
then it must have been me creating it when investigating the issue, so I tricked myself.
I can avoid the double printing by
package buttontextexpressionissue.view.backing;
public class SomePage
    String myCButtonText = null;
    boolean called = false;
     public String getMyCButtonText()
                if (!called) {
                    System.out.println("SomePage.getMyCButtonText() : begin");
                    called=true;
                    myCButtonText= "myCButton text";
                return myCButtonText;
    public void setMyCButtonText(String myCButtonText) {
        this.myCButtonText = myCButtonText;
}Frank