title: Spring Integration Suppressing Exceptions while splitting over iterator
body: <p>Take for instance the following scenario:
  I split a message over an Iterator. If an exception is thrown inside a <code>.handle()</code> while iterating over an element, all the remaining elements are skipped and the next message is obtained.
  I need to suppress any possible exceptions so that all elements in the iterator are processed.</p>
  
  <p>Since I am using Iterator instead of List, for instance, I cannot solve this using <code>.aggregate()</code>.</p>
  
  <p>Please, how can I manage to get the desired behaviour...?</p>
  
  <ul>
  <li>Spring Boot Starter Integration 1.3.0</li>
  <li>Spring Integration 4.2.1</li>
  <li>Java DSL 1.1.1</li>
  </ul>
  
  <p>Thanks in advance!</p>