code: public static String htmlEncode(String input)
  	{
  		if (input == null)
  		{
  			return "";
  		}
  		StringBuffer retval = new StringBuffer(input);
  		StringSupport.replaceAll(retval, "&", "&amp;");
  		StringSupport.replaceAll(retval, "<", "&lt;");
  		StringSupport.replaceAll(retval, ">", "&gt;");
  		StringSupport.replaceAll(retval, "\"", "&quot;");
  		return retval.toString();
  	}
docs: Encodes a String in format suitable for use in HTML form input.
  Disables malicious input used for cross-scripting hacks.
  Converts null to empty string;
  
  @param input
  @return