title: Merging two but streams obtained from docx
body: <p>I used a service to get one docx in binary content and I have one docx file which I'am able to convert to binary content now
  If I try to write both to byte array and when I open either I found only one document or I was not able to open the document .The code can be seen below</p>
  <pre><code>    Byte [] a = (byte[])obj1;
  Byte [] b = (byte[])obj2;
      Outputstream op= new outputstream();
  Try {
  Op.write(a);
  Op write(b);
  Byte[] combined = op.toByteArray();
  </code></pre>
  <p>Final byte array - combined either contain only one docx file or It became s unreadable.
  Need a solution without any extra jars.</p>