title: Object oriented design patterns for parsing text files?
body: <p>As part of a software package I'm working on, I need to implement a parser for application specific text files. I've already specified the grammar for these file on paper, but am having a hard time translating it into easily readable/updatable code (right now just it passes each line through a huge number of switch statements).</p>
  
  <p>So, are there any good design patterns for implementing a parser in a Java style OO environment?</p>