code: @SuppressWarnings("deprecation")
  	protected String getExpressionUrl(String expression) {
  		String template = _config.getValue(Property.AUDIT_METRIC_URL_TEMPLATE.getName(), Property.AUDIT_METRIC_URL_TEMPLATE.getDefaultValue());
  		try {
  			expression = URLEncoder.encode(expression, "UTF-8");
  		} catch (Exception ex) {
  			expression = URLEncoder.encode(expression);
  		}
  		return template.replaceAll("\\$expression\\$", expression);
  	}
docs: Returns the URL linking back to the expression for use in alert notification.
  
  @param   expression  The expression for which the URL has to be created.
  
  @return  The fully constructed URL for the expression.