/**
  * Calculates the similarity between entity a and b
  *
  * @param a Entity a
  * @param b Entity b
  * @return Similarity between a and b
  * @throws Exception
  */
 public double calcSimilarity(Entity a, Entity b) throws Exception {
   double sim = similarityMeasure.calcSimilarity(a, b, entityContext);
   return sim;
 }
 public String getIdentifier() {
   return similarityMeasure.getIdentifier() + ":" + entityContext.getIdentifier();
 }