title: hava regex starts with and ends with and skipping a specific charachter
body: <p>I would like to find a string that starts and ends with a specific special character but skipping when another specific charachter.</p>
  <p>I want to find any string that starts with &quot;hello&quot;and ends with a dot &quot;.&quot; but not like &quot;here end.&quot; this must be skipped when &quot;here end&quot; is preceding the dot &quot;.&quot;.</p>
  <p>Sample :</p>
  <pre><code>String para = &quot;XXXX@gxxl.com. this will share the costs and hello you  the initial here end. must be carrefully done.Keep going.&quot;
  </code></pre>
  <p>I tried the following regex but its not working:</p>
  <pre><code>hello.+?((?=([.]))
  </code></pre>
  <p>I got this :</p>
  <pre><code>&quot;hello you  the initial here end.&quot;
  </code></pre>
  <p>but this is required :</p>
  <pre><code>&quot;hello you  the initial here end. must be carrefully done.&quot;
  </code></pre>