/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
import java.io.IOException;
import java.io.LineNumberReader;
import java.io.PrintWriter;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;
/**
* Utility class for working with xml data
*
* Implementation is heavily based on org.apache.log4j.helpers.Transform
*
* @author The Apache MINA Project (dev@mina.apache.org)
* @version $Rev: 686610 $, $Date: 2008-08-17 15:31:25 +0200 (Sun, 17 Aug 2008) $
*/
public class Transform {
private static final String CDATA_START = "<![CDATA[";
private static final String CDATA_END = "]]>";
private static final String CDATA_PSEUDO_END = "]]>";
private static final String CDATA_EMBEDED_END = CDATA_END + CDATA_PSEUDO_END + CDATA_START;
private static final int CDATA_END_LEN = CDATA_END.length();
/**
* This method takes a string which may contain HTML tags (ie,
* <b>, <table>, etc) and replaces any
* '<', '>' , '&' or '"'
* characters with respective predefined entity references.
*
* @param input The text to be converted.
* @return The input string with the special characters replaced.
* */
static public String escapeTags(final String input) {
// Check if the string is null, zero length or devoid of special characters
// if so, return what was sent in.
if(input == null
|| input.length() == 0
|| (input.indexOf('"') == -1 &&
input.indexOf('&') == -1 &&
input.indexOf('<') == -1 &&
input.indexOf('>') == -1)) {
return input;
}
StringBuilder buf = new StringBuilder(input.length() + 6);
char ch;
int len = input.length();
for(int i=0; i < len; i++) {
ch = input.charAt(i);
if (ch > '>') {
buf.append(ch);
} else if(ch == '<') {
buf.append("<");
} else if(ch == '>') {
buf.append(">");
} else if(ch == '&') {
buf.append("&");
} else if(ch == '"') {
buf.append(""");
} else {
buf.append(ch);
}
}
return buf.toString();
}
/**
* Ensures that embeded CDEnd strings (]]>) are handled properly
* within message, NDC and throwable tag text.
*
* @param buf StringBuffer holding the XML data to this point. The
* initial CDStart (<![CDATA[) and final CDEnd (]]>) of the CDATA
* section are the responsibility of the calling method.
* @param str The String that is inserted into an existing CDATA Section within buf.
* */
static public void appendEscapingCDATA(final StringBuffer buf,
final String str) {
if (str != null) {
int end = str.indexOf(CDATA_END);
if (end < 0) {
buf.append(str);
} else {
int start = 0;
while (end > -1) {
buf.append(str.substring(start, end));
buf.append(CDATA_EMBEDED_END);
start = end + CDATA_END_LEN;
if (start < str.length()) {
end = str.indexOf(CDATA_END, start);
} else {
return;
}
}
buf.append(str.substring(start));
}
}
}
/**
* convert a Throwable into an array of Strings
* @param throwable
* @return string representation of the throwable
*/
public static String[] getThrowableStrRep(Throwable throwable) {
StringWriter sw = new StringWriter();
PrintWriter pw = new PrintWriter(sw);
throwable.printStackTrace(pw);
pw.flush();
LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
ArrayList<String> lines = new ArrayList<String>();
try {
String line = reader.readLine();
while(line != null) {
lines.add(line);
line = reader.readLine();
}
} catch(IOException ex) {
lines.add(ex.toString());
}
String[] rep = new String[lines.size()];
lines.toArray(rep);
return rep;
}
}
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