title: java mongodb combine date substraction
body: <p>I can't create SQL-like mongo condition like:</p>
  <pre><code>WHERE DATE1 &lt; sysdate - DATE2
  </code></pre>
  <p>DATE_1 and DATE_2 are mongo fields.</p>
  <p>i think it would be something like that</p>
  <pre><code>collection.find(lt(&quot;DATE1&quot;, LocalDateTime.now() - /* what must be here? */));
  </code></pre>