title: Join comma if not empty or null
body: <p>I saw <a href="https://stackoverflow.com/questions/63150/whats-the-best-way-to-build-a-string-of-delimited-items-in-java">this </a> answer of how to join String[] to comma separated string.</p>
  
  <p>However I need the util to join the string in the array <strong>only</strong> if the values are not empty.</p>
  
  <p>What is the best way to do it? without looping before on the String[] to remove. I prefer one method that does both.</p>
  
  <p><strong>EDITED</strong></p>
  
  <p>for instance:</p>
  
  <pre><code>I, love, , u
  </code></pre>
  
  <p>will be:</p>
  
  <pre><code> I love u
  </code></pre>