### Question:
DictionaryManager implements IDictionaryManager, ILoadableManager { @Override public synchronized void invalidateDictionaries(SailfishURI ... uris) { if (uris == null || uris.length == 0) { dicts.clear(); dictionaryIds.clear(); factories.clear(); invalidateEvent(Collections.unmodifiableSet(dicts.keySet())); logger.info("All dictionaries have been invalidated"); } else { for (SailfishURI uri : uris) { dicts.remove(uri); dictionaryIds.remove(uri); factories.remove(uri); } invalidateEvent(new HashSet<>(Arrays.asList(uris))); StringBuilder builder = new StringBuilder("Dictionaries ") .append(Arrays.toString(uris)) .append(" have been invalidated"); logger.info("{}", builder); } } DictionaryManager(IWorkspaceDispatcher workspaceDispatcher, UtilityManager utilityManager); @Override synchronized Set<SailfishURI> getDictionaryURIs(); @Override synchronized Set<SailfishURI> getDictionaryURIs(String pluginAlias); @Override synchronized List<SailfishURI> getCachedDictURIs(); @Override synchronized Map<SailfishURI, String> getDictionaryLocations(); @Override void load(ILoadableManagerContext context); @Override void finalize(ILoadableManagerContext context); @Override synchronized IDictionaryStructure getDictionary(SailfishURI uri); @Override synchronized DictionarySettings getSettings(SailfishURI uri); @Override synchronized IMessageFactory getMessageFactory(SailfishURI uri); @Override String toString(); @Override synchronized void invalidateDictionaries(SailfishURI ... uris); @Override IDictionaryStructure createMessageDictionary(String pathName); @Override IMessageFactory createMessageFactory(); @Override UtilityInfo getUtilityInfo(SailfishURI dictionaryURI, SailfishURI utilityURI, Class<?>... argTypes); @Override UtilityInfo getUtilityInfo(SailfishURI dictionaryURI, SailfishURI utilityURI, long line, long uid, String column, AlertCollector alertCollector, Class<?>... argTypes); @Override Set<SailfishURI> getUtilityURIs(SailfishURI dictionaryURI); @Override long getDictionaryId(SailfishURI uri); @Override void subscribeForEvents(IDictionaryManagerListener listener); @Override void unSubscribeForEvents(IDictionaryManagerListener listener); void invalidateEvent(Set<SailfishURI> uris); void createEvent(SailfishURI uri); @Override IDictionaryRegistrator registerDictionary(String title, boolean overwrite);  }### Answer:
@Test public void testInvalidateDictionaries() { SailfishURI dictionaryURI = SailfishURI.unsafeParse("Example"); IDictionaryManager manager = SFLocalContext.getDefault().getDictionaryManager(); IDictionaryStructure dictFirst = manager.getDictionary(dictionaryURI); IDictionaryStructure dictSecond = manager.getDictionary(dictionaryURI); Assert.assertEquals(dictFirst, dictSecond); manager.invalidateDictionaries(); dictSecond = manager.getDictionary(dictionaryURI); Assert.assertThat(dictFirst, CoreMatchers.not(dictSecond)); manager.invalidateDictionaries(dictionaryURI); dictSecond = manager.getDictionary(dictionaryURI); Assert.assertThat(dictFirst, CoreMatchers.not(dictSecond)); }