title: How to convert XMLGregorianCalander to Epoch-Time or other fixed integer ?
body: <p>Is there a library that will allow me to easily convert the java type XMLGregorianCalander to Epoch time (The number of seconds since 01-01-1970 00:00:00?)? Or any other fixed integer for that matter? </p>
  
  <p>If not, is there some neat, boiler plate code to do this? 
  This seems like too common a use case to be writing from scratch... </p>
  
  <p>Thank you very much for your answers. </p>