code: public boolean revokeResourcePermission(String subjectid, String resourcePath) {
  		if (!StringUtils.isBlank(subjectid) && getResourcePermissions().containsKey(subjectid) &&
  				!StringUtils.isBlank(resourcePath)) {
  			// urlDecode resource path
  			resourcePath = Utils.urlDecode(resourcePath);
  			getResourcePermissions().get(subjectid).remove(resourcePath);
  			if (getResourcePermissions().get(subjectid).isEmpty()) {
  				getResourcePermissions().remove(subjectid);
  			}
  			return true;
  		}
  		return false;
  	}
docs: Revokes a permission for given subject.
  @param subjectid subject id
  @param resourcePath resource path or object type
  @return true if successful