code: protected String buildAllAttributes(TagAttributes tagAttributes, MessageSource messageSource, boolean html5Validation) {
  		StringBuilder allAttribs = new StringBuilder();
  		allAttribs.append(AttributeUtils.buildAttributes(tagAttributes));
  		allAttribs.append(getElementId());
  		allAttribs.append(getTabIndexTag());
  		if (html5Validation) {
  			allAttribs.append(buildRequiredAttribute());
  			allAttribs.append(buildFcRequiredMessage(messageSource));
  		}
  		allAttribs.append(buildSizeAttribute());
  		// help-text
  		if (!StringUtils.isEmpty(helpText)) {
  			allAttribs.append(
  					AttributeUtils.buildAttributes(new TagAttributes("aria-describedby", 
  							parent.getConfig().getFormBuilder().getHelpBlockId(this))));
  		}
  		return allAttribs.toString();
  	}
docs: builds attribs, elementId, TabIndex