public Collection<PearsonDictionaryEntry> filter() {
		List<PearsonDictionaryEntry> retVal = new ArrayList<PearsonDictionaryEntry>();
		for (PearsonDictionaryEntry entry : entries) {
			if (entry.getHeadword() != null && headword != null) {
				if (entry.getHeadword().equals(headword)) {
					if (posTagConstrains.contains(entry.getPosTag())) {
						retVal.add(entry);
					}
				} else {
					retVal.add(entry);
				}
			}
		}
		return retVal;
	}