package util;public final class HTMLFilter { /** * Filter the specified message string for characters that are sensitive * in HTML. This avoids potential attacks caused by including JavaScript * codes in the request URL that is often reported in error messages. * * @param message The message string to be filtered */ public static String filter(String message) { if (message == null) return (null); char content[] = new char[message.length()]; message.getChars(0, message.length(), content, 0); StringBuilder result = new StringBuilder(content.length + 50); for (int i = 0; i < content.length; i++) { switch (content[i]) { case '<': result.append("<"); break; case '>': result.append(">"); break; case '&': result.append("&"); break; case '"': result.append("""); break; default: result.append(content[i]); } } return (result.toString()); }}