code: public String handleBooleanAnnotation(String annotation, Boolean value, String message, String validate) {
  
  		if (!Boolean.TRUE.equals(value))
  			return "";
  
  		// if validate contains annotation, do nothing
  		if (validate != null && validate.toLowerCase().matches(".*@" + annotation.toLowerCase() + ".*"))
  			return "";
  
  		String result = " @" + annotation;
  
  		// set message if not set
  		if (message != null) {
  			result += "(" + (message.toLowerCase().matches(".*message.*") ? "" : "message=") + message + ")";
  		}
  
  		return result + " ";
  	}
docs: Handles all boolean validation annotations (Future, Past, Email, ...).
  
  @param annotation
  the name of the annotation
  @param value
  annotation is set or not
  @param validate
  the validate string
  @return annotation validation string