title: Delete duplicate words in a big text file - Java
body: <p>I have text file with a size of over 50gb.
  Now i want to delete the duplicate words.
  But I have heard, that i need very much RAM to load every Word from the text file into an Hash Set.
  Can you tell me a very good way to delete every duplicate word from the text file?
  The Words are sorted by a white space, like this.</p>
  
  <pre><code>word1 word2 word3 ... ... 
  </code></pre>