title: Empty string with multiple blank problem in JSF - SPRING - HIBERNATE
body: <p>i have a simple problme.
  I need to catch when a user enter an empty string in a form and display the appropriate error message.
  I'm trying with jsf required attribute, but if the user enter "   " a string like that the validation go next without error.
  I had try Spring annotation @NotNull and Hibernate @NotEmpty, but nothing solve the problem.
  Any idea?</p>