title: Reading hidden content from a pdf in java
body: <p>I have several pdfs with some codes scatterred across (no fixed position) as below:</p>
  
  <pre><code>oneCode=abcd
  twoCode=4566
  </code></pre>
  
  <p>Also, the font color of the text is white (same as the background color of the PDF). So they are invisible to eye. </p>
  
  <p>I want to write a program to parse the pdf using the keys (first part of the complete word e.g. oneCode, twoCode, etc.) and get the corresponding values (e.g. abcd, 4566, etc.).</p>
  
  <p>Is such a functionality available in any open source pdf parsers like PDFBox, iText, etc. ?</p>
  
  <p>Can any one please point to a example ?</p>
  
  <p>Thanks for reading!</p>