code: @Override
      public Builder claimFrom(JwtToken jwt, String claimName) throws InvalidClaimException, InvalidTokenException {
          isValidToken(jwt);
          if (JwtUtils.isNullEmpty(claimName)) {
              String err = Tr.formatMessage(tc, "JWT_INVALID_CLAIM_ERR", new Object[] { claimName });
              throw new InvalidClaimException(err);
          }
          if (jwt.getClaims().get(claimName) != null) {
              claims.put(claimName, jwt.getClaims().get(claimName));
          }
          // else {
          // String err = Tr.formatMessage(tc, "JWT_INVALID_CLAIM_VALUE_ERR", new
          // Object[] { claimName, "null" });
          // throw new InvalidClaimException(err);
          // }
          return this;
      }
docs: /*
  (non-Javadoc)
  
  @see com.ibm.ws.security.jwt.internal.Builder#claimFrom(com.ibm.websphere.security.jwt.JwtToken, java.lang.String)