com.devexperts.qd
Interface StableSubscriptionFilter

All Superinterfaces:
SubscriptionFilter
All Known Implementing Classes:
PatternFilter

public interface StableSubscriptionFilter
extends SubscriptionFilter

Stable subscription filter has a fixed logic (it cannot depend on any external resources or state) and it is reconstructible from string by SubscriptionFilterFactory.


Method Summary
 StableSubscriptionFilter toStableFilter()
          Returns a stable filter that is the same or more encompassing as this filter.
 
Methods inherited from interface com.devexperts.qd.SubscriptionFilter
acceptRecord
 

Method Detail

toStableFilter

StableSubscriptionFilter toStableFilter()
Returns a stable filter that is the same or more encompassing as this filter. It is always safe to return null, which means that this filter is not stable and the only stable extension of it consitutes all symbols. Stable filters must return this as a result of this method. The result of this method satisfies the following constrains:
  1. Result must be stable filter, that is result is null or result.toStableFilter() == result
  2. Result must be more encompasing, that is result is null or this.acceptRecord(...) implies result.acceptRecord(...).
  3. Result must be reconstructible from string, that is result is null or result.toString() must parse back to the same filter via data scheme's SubscriptionFilterFactory.