[faces-dev] change of specification or an error ?

[LInda hackkanan <lindahackkanan@xxxxxxxx>]

 

I have a book I am using to practice Java Server Faces.

In this book  the example code given is

 

  <h:commandButton
      value="#{'Go ' + xyz.submit}" 
      action="">

 

Using the above syntax I was getting the error

java.lang.NumberFormatException: For input string: "Go "

 

After some intuitive guesses I changed the syntax to this.

                value="Go #{xyz.submit}"

 

This produced the expected results, so I now know how to dynamically update button label.

 

My question is ,  did the book provide me with incorrect syntax or

was there a change in the specification ?