code: @Override
      public Set<URI> listEquivalentClasses(URI classUri) {
  
          if (classUri == null)
              return ImmutableSet.of();
  
          StringBuilder strBuilder = new StringBuilder()
                  .append("select DISTINCT ?class where { \n")
                  .append("?class").append(" <").append(OWL.equivalentClass.getURI()).append("> ").append("<").append(classUri.toASCIIString()).append("> .")
                  .append(" }");
  
          return this.graphStoreManager.listResourcesByQuery(strBuilder.toString(), "class");
      }
docs: Answers a List all of URIs of the classes that are known to be equivalent to this class. Equivalence may be
  asserted in the model (using, for example, owl:equivalentClass, or may be inferred by the reasoner attached to
  the model. Note that the OWL semantics entails that every class is equivalent to itself, so when using a
  reasoning model clients should expect that this class will appear as a member of its own equivalent classes.
  
  @param classUri the URI of the class for which to list the equivalent classes
  @return the List of equivalent classes