command button validations

[charishma gottumukkula]

I am creating a small user interface where i got to validate the command buttons.For ex i have a commed button called start or stop,If nothing is selected and the command button is clicked i should get a message called "none of the items are selected"

Can anyone please help me with the sample code

[John Blanco]

Just write an action method:

<h:commandButton value="Submit" action="#{myBackingBean.submit}" />

public class MyBackingBean {
   public String submit() {
      if (...values properly set...) {
         return "success";
      }
 
      return "failure";
   }
}