package net.java.sip.communicator.util.xml;
/*
* SIP Communicator, the OpenSource Java VoIP and Instant Messaging client.
*
* Distributable under LGPL license.
* See terms of license at gnu.org.
*
* The code in this class was borrowed from the ant libs and included the
* following copyright notice:
* Copyright 2000-2004 The Apache Software Foundation
*
* Licensed 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.*;
import org.w3c.dom.*;
/**
* Writes a DOM tree to a given Writer.
*
* <p>Utility class used by net.java.sip.communicator.util.xml.XMLUtils
* and the net.java.sip.communicator.slick.runner.SipCommunicatorSlickRunner.
* </p>
*
*/
public class DOMElementWriter {
private static String lSep = System.getProperty("line.separator");
/**
* Don't try to be too smart but at least recognize the predefined
* entities.
*/
protected String[] knownEntities = {"gt", "amp", "lt", "apos", "quot"};
/**
* Writes a DOM tree to a stream in UTF8 encoding. Note that
* it prepends the <?xml version='1.0' encoding='UTF-8'?>.
* The indent number is set to 0 and a 2-space indent.
* @param root the root element of the DOM tree.
* @param out the outputstream to write to.
* @throws IOException if an error happens while writing to the stream.
*/
public void write(Element root, OutputStream out)
throws IOException
{
Writer wri = new OutputStreamWriter(out, "UTF-8");
wri.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>"+lSep);
write(root, wri, 0, " ");
wri.flush();
}
/**
* Writes a DOM tree to a stream.
*
* @param element the Root DOM element of the tree
* @param out where to send the output
* @param indent number of
* @param indentWith string that should be used to indent the corresponding tag.
* @throws IOException if an error happens while writing to the stream.
*/
public void write(Node element, Writer out, int indent,
String indentWith)
throws IOException
{
// Write indent characters
for (int i = 0; i < indent; i++) {
out.write(indentWith);
}
if(element.getNodeType() == Node.COMMENT_NODE)
{
out.write("<!--");
out.write(encode(element.getNodeValue()));
out.write("-->");
}
else
{
// Write element
out.write("<");
out.write(((Element)element).getTagName());
// Write attributes
NamedNodeMap attrs = element.getAttributes();
for (int i = 0; i < attrs.getLength(); i++)
{
Attr attr = (Attr) attrs.item(i);
out.write(" ");
out.write(attr.getName());
out.write("=\"");
out.write(encode(attr.getValue()));
out.write("\"");
}
out.write(">");
}
// Write child elements and text
boolean hasChildren = false;
NodeList children = element.getChildNodes();
for (int i = 0
; element.hasChildNodes()
&& i < children.getLength()
; i++)
{
Node child = children.item(i);
switch (child.getNodeType()) {
case Node.ELEMENT_NODE: case Node.COMMENT_NODE:
if (!hasChildren) {
out.write(lSep);
hasChildren = true;
}
write(child, out, indent + 1, indentWith);
break;
case Node.TEXT_NODE:
//if this is a new line don't print it as we print our own.
if(child.getNodeValue() != null
&& ( child.getNodeValue().indexOf("\n") == -1
|| child.getNodeValue().trim().length() != 0))
out.write(encode(child.getNodeValue()));
break;
case Node.CDATA_SECTION_NODE:
out.write("<![CDATA[");
out.write(encodedata(((Text) child).getData()));
out.write("]]>");
break;
case Node.ENTITY_REFERENCE_NODE:
out.write('&');
out.write(child.getNodeName());
out.write(';');
break;
case Node.PROCESSING_INSTRUCTION_NODE:
out.write("<?");
out.write(child.getNodeName());
String data = child.getNodeValue();
if (data != null && data.length() > 0) {
out.write(' ');
out.write(data);
}
out.write("?>");
break;
}
}
// If we had child elements, we need to indent before we close
// the element, otherwise we're on the same line and don't need
// to indent
if (hasChildren) {
for (int i = 0; i < indent; i++) {
out.write(indentWith);
}
}
// Write element close
if(element.getNodeType() == Node.ELEMENT_NODE)
{
out.write("</");
out.write(((Element)element).getTagName());
out.write(">");
}
out.write(lSep);
out.flush();
}
/**
* Escape <, > & ', " as their entities and
* drop characters that are illegal in XML documents.
*
* @param value the value to encode
*
* @return a String containing the encoded element.
*/
public String encode(String value) {
StringBuffer sb = new StringBuffer();
int len = value.length();
for (int i = 0; i < len; i++) {
char c = value.charAt(i);
switch (c) {
case '<':
sb.append("<");
break;
case '>':
sb.append(">");
break;
case '\'':
sb.append("'");
break;
case '\"':
sb.append(""");
break;
case '&':
int nextSemi = value.indexOf(";", i);
if (nextSemi < 0
|| !isReference(value.substring(i, nextSemi + 1))) {
sb.append("&");
} else {
sb.append('&');
}
break;
default:
if (isLegalCharacter(c)) {
sb.append(c);
}
break;
}
}
return sb.substring(0);
}
/**
* Drop characters that are illegal in XML documents.
*
* <p>Also ensure that we are not including an <tt>]]></tt>
* marker by replacing that sequence with
* <tt>]]></tt>.</p>
*
* <p>See XML 1.0 2.2 <a
* href="http://www.w3.org/TR/1998/REC-xml-19980210#charsets">http://www.w3.org/TR/1998/REC-xml-19980210#charsets</a> and
* 2.7 <a
* href="http://www.w3.org/TR/1998/REC-xml-19980210#sec-cdata-sect">http://www.w3.org/TR/1998/REC-xml-19980210#sec-cdata-sect</a>.</p>
*
* @param value the value to encode
*
* @return a String containing the encoded value.
*/
public String encodedata(final String value) {
StringBuffer sb = new StringBuffer();
int len = value.length();
for (int i = 0; i < len; ++i) {
char c = value.charAt(i);
if (isLegalCharacter(c)) {
sb.append(c);
}
}
String result = sb.substring(0);
int cdEnd = result.indexOf("]]>");
while (cdEnd != -1) {
sb.setLength(cdEnd);
sb.append("]]>")
.append(result.substring(cdEnd + 3));
result = sb.substring(0);
cdEnd = result.indexOf("]]>");
}
return result;
}
/**
* Is the given argument a character or entity reference?
*
*
* @param ent the string whose nature we need to determine.
*
* @return true if ent is an entity reference and false otherwise.
*/
public boolean isReference(String ent) {
if (!(ent.charAt(0) == '&') || !ent.endsWith(";")) {
return false;
}
if (ent.charAt(1) == '#') {
if (ent.charAt(2) == 'x') {
try {
Integer.parseInt(ent.substring(3, ent.length() - 1), 16);
return true;
} catch (NumberFormatException nfe) {
return false;
}
} else {
try {
Integer.parseInt(ent.substring(2, ent.length() - 1));
return true;
} catch (NumberFormatException nfe) {
return false;
}
}
}
String name = ent.substring(1, ent.length() - 1);
for (int i = 0; i < knownEntities.length; i++) {
if (name.equals(knownEntities[i])) {
return true;
}
}
return false;
}
/**
* Is the given character allowed inside an XML document?
*
* <p>See XML 1.0 2.2 <a
* href="http://www.w3.org/TR/1998/REC-xml-19980210#charsets">
* http://www.w3.org/TR/1998/REC-xml-19980210#charsets</a>.</p>
*
* @since 1.10, Ant 1.5
*
* @param c the character hose nature we'd like to determine.
*
* @return true if c is a legal character and false otherwise
*/
public boolean isLegalCharacter(char c) {
if (c == 0x9 || c == 0xA || c == 0xD) {
return true;
} else if (c < 0x20) {
return false;
} else if (c <= 0xD7FF) {
return true;
} else if (c < 0xE000) {
return false;
} else if (c <= 0xFFFD) {
return true;
}
return false;
}
}