/*
* JBoss DNA (http://www.jboss.org/dna)
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
* See the AUTHORS.txt file in the distribution for a full listing of
* individual contributors.
*
* JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
* is licensed to you under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* JBoss DNA is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.dna.common.text;
import java.text.CharacterIterator;
import java.text.StringCharacterIterator;
import java.util.HashMap;
import java.util.Map;
/**
* An encoder useful for converting text to be used within XML attribute values.
* The following translations will be performed:
* <table cellspacing="0" cellpadding="1" border="1">
* <tr>
* <th>Raw (Unencoded)<br/>Character</th>
* <th>Translated (Encoded)<br/>Entity</th>
* </tr>
* <tr>
* <td> & </td>
* <td> &amp; </td>
* </tr>
* <tr>
* <td> < </td>
* <td> &lt; </td>
* </tr>
* <tr>
* <td> > </td>
* <td> &gt; </td>
* </tr>
* <tr>
* <td> " </td>
* <td> &quot; </td>
* </tr>
* <tr>
* <td> ' </td>
* <td> &#039; </td>
* </tr>
* <tr>
* <td>All Others</td>
* <td>No Translation</td>
* </tr>
* </table>
* </p>
*/
public class XmlValueEncoder implements TextEncoder, TextDecoder {
private static final Map<String, Character> SPECIAL_ENTITIES;
static {
SPECIAL_ENTITIES = new HashMap<String, Character>();
SPECIAL_ENTITIES.put("quot", '"');
SPECIAL_ENTITIES.put("gt", '>');
SPECIAL_ENTITIES.put("lt", '<');
SPECIAL_ENTITIES.put("amp", '&');
}
/**
* {@inheritDoc}
*
* @see org.jboss.dna.common.text.TextEncoder#encode(java.lang.String)
*/
public String encode( String text ) {
if (text == null) return null;
StringBuilder sb = new StringBuilder();
CharacterIterator iter = new StringCharacterIterator(text);
for (char c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) {
switch (c) {
case '&':
sb.append("&");
break;
case '"':
sb.append(""");
break;
case '<':
sb.append("<");
break;
case '>':
sb.append(">");
break;
case '\'':
sb.append("'");
break;
default:
sb.append(c);
}
}
return sb.toString();
}
/**
* {@inheritDoc}
*
* @see org.jboss.dna.common.text.TextDecoder#decode(java.lang.String)
*/
public String decode( String encodedText ) {
if (encodedText == null) return null;
StringBuilder sb = new StringBuilder();
CharacterIterator iter = new StringCharacterIterator(encodedText);
for (char c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) {
if (c == '&') {
int index = iter.getIndex();
do {
c = iter.next();
}
while (c != CharacterIterator.DONE && c != ';');
// We found a closing semicolon
if (c == ';') {
String s = encodedText.substring(index + 1, iter.getIndex());
if (SPECIAL_ENTITIES.containsKey(s)) {
sb.append(SPECIAL_ENTITIES.get(s));
continue;
}
if (s.length() > 0 && s.charAt(0) == '#') {
try {
sb.append((char) Short.parseShort(s.substring(1, s.length())));
continue;
}
catch (NumberFormatException nfe) {
// This is possible in malformed encodings, but let it fall through
}
}
}
// Malformed encoding, restore state and pass poorly encoded data back
c = '&';
iter.setIndex(index);
}
sb.append(c);
}
return sb.toString();
}
}