Consider the following code:
This will tell the user to call isPresent() on the optional before calling get() on it. This happens because the call to isEmpty() is performed on a different symbolic value than the call to get() because of the repeated method call. However, a user might reasonably assume that it's because isEmpty() is used instead of isPresent().
To avoid this confusion, the message should mention isEmpty() as well as isPresent().
The rule description should also be amended to explain that results of multiple method calls will be treated as different values as a method might potentially return a different value each time (and that the current rule implementation currently treats all methods as if they do so). With a noncompliant-compliant example pair showing how storing a method's result in a local variable fix the issue.