title: Merge Pdf Files Using PDFBox
body: <p>I have to merge two pdf Files using PdfBox of Apache. I have taken physical pdf files to do so.
  Below is the code:</p>
  
  <pre><code>PDFMergerUtility ut = new PDFMergerUtility();
  ut.addSource(path1);
  ut.addSource(path2);
  ut.setDestinationFileName(path3);
  ut.mergeDocuments(MemoryUsageSetting.setupMainMemoryOnly());
  </code></pre>
  
  <p>Files are merged perfectly but then have some constraints as below:</p>
  
  <ol>
  <li>I am creating 1st file in the code itself,so it is PDDocument object.</li>
  <li>The file which I have to merge with 1st file is in byte array format.</li>
  <li>I don't need to save the merged files but need convert it as byte array.</li>
  </ol>
  
  <p>Please anyone help me achieve this requirement.</p>