ADDITIONAL SYSTEM INFORMATION :
Any OS, Java 8, 11

A DESCRIPTION OF THE PROBLEM :
When an LDAP operation fails for technical reasons (read timeout, broken connection) the aforemetioned class will unfortunately use a general NamingException to signal this to client code. The client code has no way to distinguish this from other NamingExceptions. The CommunicationException has been especially designed for this:
  * This exception is thrown when the client is
  * unable to communicate with the directory or naming service.
  * The inability to communicate with the service might be a result
  * of many factors, such as network partitioning, hardware or interface problems,
  * failures on either the client or server side.
  * This exception is meant to be used to capture such communication problems.

The RFE is to turn:
        if (result == null) {
            throw new NamingException(String.format(TIMEOUT_MSG_FMT, millis));
        }
        // Unexpected EOF can be caused by connection closure or cancellation
        if (result == EOF) {
            throw new NamingException(CLOSE_MSG);
        }
into
        if (result == null) {
            throw new CommunicationException(String.format(TIMEOUT_MSG_FMT, millis));
        }
        // Unexpected EOF can be caused by connection closure or cancellation
        if (result == EOF) {
            throw new CommunicationException(CLOSE_MSG);
        }

which will give the client a change to recover from by retry the operation because it did not fail for LDAP reasons.

This has been reported with Apache Tomcat: https://www.mail-archive.com/users@tomcat.apache.org/msg138297.html