code: public final byte[] getClassDigest(String name) {
      byte[] digest = digestLookup.get(name);
      if (digest == null) {
        try {
          if (beginLookup(pendingDigest, name)) {
            try {
              digest = service.getClassDigest(name, jobId);
              digestLookup.put(name, digest);
            } finally {
              endLookup(pendingDigest, name);
            }
          } else {
            digest = digestLookup.get(name);
          }
        } catch (SecurityException e) {
          logger.error("Could not get class digest", e);
        } catch (RemoteException e) {
          logger.error("Could not get class digest", e);
        }
      }
      return digest;
    }
docs: Gets the digest associated with a given class.
  @param name The name of the class.
  @return The class digest.