title: Extracting string from within round brackets in Java with regex
body: <p>I'm trying to extract a string from round brackets.<br>
  Let's say, I have <code>John Doe (123456789)</code> and I want to output the string <code>123456789</code> only.</p>
  
  <p>I have found <a href="https://stackoverflow.com/questions/4006113/java-regular-expression-to-extract-content-within-square-brackets">this link</a> and this regex:</p>
  
  <pre><code>/\(([^)]+)\)/g
  </code></pre>
  
  <p>However, I wasn't able to figure out how to get the wanted result.  </p>
  
  <p>Any help would be appreciated. Thanks!</p>