title: Java class organization
body: <p>Reading this java text and the authors advise thinking about the package org leaving only the classes really required to be open to the rest of the world as public. </p>
  
  <p>I think I get the point that bit exposing what is not needed allows changing stuff later without breaking client code - but, I can't think of an example - </p>
  
  <p>If a package let's say has a couple of entities or classes each providing a set of functionality - would the public facing class then have to orchestrate all the communication with the external world? </p>
  
  <p>Any examples or guidance would be appreciated!!!</p>