code: private static DeleteRequestType checkType(
  			final HttpServletRequest request,
  			final DeleteResponse deleteResponse) {
  		{
  			final String sType = request
  					.getParameter(ProtocolConstants.Parameters.Delete.TYPE);
  			if (sType != null) {
  				if (DeleteRequestType.USER.getIdentifier().equals(sType)) {
  					return DeleteRequestType.USER;
  				} else if (DeleteRequestType.FOLLOW.getIdentifier().equals(
  						sType)) {
  					return DeleteRequestType.FOLLOW;
  				} else if (DeleteRequestType.STATUS_UPDATE.getIdentifier()
  						.equals(sType)) {
  					return DeleteRequestType.STATUS_UPDATE;
  				} else {
  					deleteResponse.typeInvalid(sType);
  				}
  			} else {
  				deleteResponse.typeMissing();
  			}
  
  			return null;
  		}
  
  	}
docs: check if the request contains a valid delete request type
  
  @param request
  Tomcat servlet request
  @param deleteResponse
  delete response object
  @return delete request type<br>
  <b>null</b> if the delete request type is invalid