There holds: If B is a synonym for A (A -> B) then A is also a synonym for B (B -> A). There does not necessarily hold: A -> B, B -> C then A -> C.
Loading typically takes some 1.5 secs, so should be done only once per (server) program execution, using a singleton pattern. Once loaded, a synonym lookup via {@link #getSynonyms(String)}takes constant time O(1). A loaded default synonym map consumes about 10 MB main memory. An instance is immutable, hence thread-safe.
This implementation borrows some ideas from the Lucene Syns2Index demo that Dave Spencer originally contributed to Lucene. Dave's approach involved a persistent Lucene index which is suitable for occasional lookups or very large synonym tables, but considered unsuitable for high-frequency lookups of medium size synonym tables.
Example Usage:
String[] words = new String[] { "hard", "woods", "forest", "wolfish", "xxxx"}; SynonymMap map = new SynonymMap(new FileInputStream("samples/fulltext/wn_s.pl")); for (int i = 0; i < words.length; i++) { String[] synonyms = map.getSynonyms(words[i]); System.out.println(words[i] + ":" + java.util.Arrays.asList(synonyms).toString()); } Example output: hard:[arduous, backbreaking, difficult, fermented, firmly, grueling, gruelling, heavily, heavy, intemperately, knockout, laborious, punishing, severe, severely, strong, toilsome, tough] woods:[forest, wood] forest:[afforest, timber, timberland, wood, woodland, woods] wolfish:[edacious, esurient, rapacious, ravening, ravenous, voracious, wolflike] xxxx:[]
@see prologdb man page
@see Dave's synonym demo site
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