title: Diff of two very large text files
body: <p>I have to text files:</p>
  
  <pre><code>file one: 400gb
  file two: 411gb
  </code></pre>
  
  <p>These files are database dumps in rdf format.
  The bigger file is the newer and it has new 
  data. 11gb of the data are new.</p>
  
  <p>I want to do a file diff to get this new 11gb
  of data to import the new data into my database
  without touching the old.</p>
  
  <p>How can i do it efficiently using java?</p>