1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package util; 18 19 /** 20 * HTML filter utility. 21 * 22 * @author Craig R. McClanahan 23 * @author Tim Tye 24 * @version $Revision: 664175 $ $Date: 2008-06-06 18:43:44 -0400 (Fri, 06 Jun 2008) $ 25 */ 26 27 public final class HTMLFilter { 28 29 30 /** 31 * Filter the specified message string for characters that are sensitive 32 * in HTML. This avoids potential attacks caused by including JavaScript 33 * codes in the request URL that is often reported in error messages. 34 * 35 * @param message The message string to be filtered 36 */ 37 public static String filter(String message) { 38 39 if (message == null) 40 return (null); 41 42 char content[] = new char[message.length()]; 43 message.getChars(0, message.length(), content, 0); 44 StringBuffer result = new StringBuffer(content.length + 50); 45 for (int i = 0; i < content.length; i++) { 46 switch (content[i]) { 47 case '<': 48 result.append("<"); 49 break; 50 case '>': 51 result.append(">"); 52 break; 53 case '&': 54 result.append("&"); 55 break; 56 case '"': 57 result.append("""); 58 break; 59 default: 60 result.append(content[i]); 61 } 62 } 63 return (result.toString()); 64 65 } 66 67 68 } 69