Rohit Kochar - 2007-09-24

I am trying to find the relation among two nouns using jwnl and wordnet but whenever i try to use findrelationship() method of class RelationshipFinder i get an NULL Pointer Exception
This method always throws an exception whenever i try to find 
HYPERNYM or HYPONYM type of realtion.I am using Wordnet 2.0 and jwnl 1.3.

The code that i tried is as follows..

public static void main(String args[])
IndexWord DOG;
IndexWord CAT;
String propsFile = args[0];
try {
JWNL.initialize(new FileInputStream(propsFile));
} catch (Exception ex) {}
DOG = Dictionary.getInstance().getIndexWord(POS.NOUN, "dog");
CAT = Dictionary.getInstance().lookupIndexWord(POS.NOUN, "cat");
RelationshipFinder r=RelationshipFinder.getInstance();
RelationshipList list =r.findRelationships(CAT.getSense(1), DOG.getSense(1),PointerType.HYPERNYM);
System.out.println("Hypernym relationship between \"" + DOG.getLemma() + "\" and \"" + CAT.getLemma() + "\":");
for (Iterator itr = list.iterator(); itr.hasNext();) {
}catch(Exception e){e.printStackTrace();};

Please help to fix this problem