001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.mina.util; 021 022import java.io.IOException; 023import java.io.LineNumberReader; 024import java.io.PrintWriter; 025import java.io.StringReader; 026import java.io.StringWriter; 027import java.util.ArrayList; 028 029/** 030 * Utility class for working with xml data 031 * 032 * Implementation is heavily based on org.apache.log4j.helpers.Transform 033 * 034 * @author <a href="http://mina.apache.org">Apache MINA Project</a> 035 */ 036public class Transform { 037 038 private static final String CDATA_START = "<![CDATA["; 039 040 private static final String CDATA_END = "]]>"; 041 042 private static final String CDATA_PSEUDO_END = "]]>"; 043 044 private static final String CDATA_EMBEDED_END = CDATA_END + CDATA_PSEUDO_END + CDATA_START; 045 046 private static final int CDATA_END_LEN = CDATA_END.length(); 047 048 /** 049 * This method takes a string which may contain HTML tags (ie, 050 * <b>, <table>, etc) and replaces any 051 * '<', '>' , '&' or '"' 052 * characters with respective predefined entity references. 053 * 054 * @param input The text to be converted. 055 * @return The input string with the special characters replaced. 056 * */ 057 static public String escapeTags(final String input) { 058 // Check if the string is null, zero length or devoid of special characters 059 // if so, return what was sent in. 060 061 if (input == null 062 || input.length() == 0 063 || (input.indexOf('"') == -1 && input.indexOf('&') == -1 && input.indexOf('<') == -1 && input 064 .indexOf('>') == -1)) { 065 return input; 066 } 067 068 StringBuilder buf = new StringBuilder(input.length() + 6); 069 char ch; 070 071 int len = input.length(); 072 for (int i = 0; i < len; i++) { 073 ch = input.charAt(i); 074 if (ch > '>') { 075 buf.append(ch); 076 } else if (ch == '<') { 077 buf.append("<"); 078 } else if (ch == '>') { 079 buf.append(">"); 080 } else if (ch == '&') { 081 buf.append("&"); 082 } else if (ch == '"') { 083 buf.append("""); 084 } else { 085 buf.append(ch); 086 } 087 } 088 return buf.toString(); 089 } 090 091 /** 092 * Ensures that embeded CDEnd strings (]]>) are handled properly 093 * within message, NDC and throwable tag text. 094 * 095 * @param buf StringBuffer holding the XML data to this point. The 096 * initial CDStart (<![CDATA[) and final CDEnd (]]>) of the CDATA 097 * section are the responsibility of the calling method. 098 * @param str The String that is inserted into an existing CDATA Section within buf. 099 * */ 100 static public void appendEscapingCDATA(final StringBuffer buf, final String str) { 101 if (str != null) { 102 int end = str.indexOf(CDATA_END); 103 if (end < 0) { 104 buf.append(str); 105 } else { 106 int start = 0; 107 while (end > -1) { 108 buf.append(str.substring(start, end)); 109 buf.append(CDATA_EMBEDED_END); 110 start = end + CDATA_END_LEN; 111 if (start < str.length()) { 112 end = str.indexOf(CDATA_END, start); 113 } else { 114 return; 115 } 116 } 117 buf.append(str.substring(start)); 118 } 119 } 120 } 121 122 /** 123 * Converts a Throwable into an array of Strings 124 * @param throwable The Throwable to convert 125 * @return string representation of the throwable 126 */ 127 public static String[] getThrowableStrRep(Throwable throwable) { 128 StringWriter sw = new StringWriter(); 129 PrintWriter pw = new PrintWriter(sw); 130 throwable.printStackTrace(pw); 131 pw.flush(); 132 LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString())); 133 ArrayList<String> lines = new ArrayList<String>(); 134 try { 135 String line = reader.readLine(); 136 while (line != null) { 137 lines.add(line); 138 line = reader.readLine(); 139 } 140 } catch (IOException ex) { 141 lines.add(ex.toString()); 142 } 143 String[] rep = new String[lines.size()]; 144 lines.toArray(rep); 145 return rep; 146 } 147 148}