As far as I know, the only way is to change the buttons in xhtml. But you can keep the order of appearance in the float:left dialog box on the Yes button.
<p:confirmDialog global="true" showEffect="fade" hideEffect="fade"> <p:commandButton value="No" type="button" styleClass="ui-confirmdialog-no" icon="ui-icon-close" /> <p:commandButton value="Yes" type="button" style="float:left;" styleClass="ui-confirmdialog-yes" icon="ui-icon-check" /> </p:confirmDialog>
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