/*
* $Id$
*
* Copyright 2006, The jCoderZ.org Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
* * Neither the name of the jCoderZ.org Project nor the names of
* its contributors may be used to endorse or promote products
* derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.jcoderz.commons.util;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.xml.transform.stream.StreamResult;
import org.xml.sax.Attributes;
/**
* This class holds utility methods for common xml topics.
*
* @author Andreas Mandel
*/
public final class XmlUtil
{
/**
* Immutable and always empty version of a
* {@link org.xml.sax.Attributes} object.
*/
public static final Attributes EMPTY_ATTRIBUTES = new EmptyAttribute();
private static final int INDENT = 2;
private static final String SPACES = " ";
/** No instances. */
private XmlUtil ()
{
// No instances.
}
/**
* Immutable implementation of a empty attribute list.
* @see Attributes
*/
private static final class EmptyAttribute
implements Attributes
{
/** {@inheritDoc} */
public int getLength ()
{
return 0;
}
/** {@inheritDoc} */
public String getLocalName (int index)
{
return null;
}
/** {@inheritDoc} */
public String getQName (int index)
{
return null;
}
/** {@inheritDoc} */
public String getType (int index)
{
return null;
}
/** {@inheritDoc} */
public String getURI (int index)
{
return null;
}
/** {@inheritDoc} */
public String getValue (int index)
{
return null;
}
/** {@inheritDoc} */
public int getIndex (String qName)
{
return -1;
}
/** {@inheritDoc} */
public String getType (String qName)
{
return null;
}
/** {@inheritDoc} */
public String getValue (String qName)
{
return null;
}
/** {@inheritDoc} */
public int getIndex (String uri, String localName)
{
return -1;
}
/** {@inheritDoc} */
public String getType (String uri, String localName)
{
return null;
}
/** {@inheritDoc} */
public String getValue (String uri, String localName)
{
return null;
}
}
/**
* Encode a string so that it can be safely used as attribute value in
* XML output.
* @param attribute the attribute value to be encoded.
* @return a string representing the attribute value that can be safely
* used in XML output.
*/
public static String attributeEscape (String attribute)
{
final StringBuffer sb = new StringBuffer();
if (attribute != null)
{
char c;
final int l = attribute.length();
for (int i = 0; i < l; i++)
{
c = attribute.charAt(i);
switch (c)
{
case '<':
sb.append("<");
break;
case '>':
sb.append(">");
break;
case '\'':
sb.append("'");
break;
case '"':
sb.append(""");
break;
case '&':
sb.append("&");
break;
default :
if (c > Byte.MAX_VALUE
|| Character.isISOControl(c))
{
sb.append("&#x");
sb.append(Integer.toHexString(c));
sb.append(';');
}
else
{
sb.append(c);
}
}
}
}
return sb.toString();
}
/**
* Encode a string so that it can be safely used as text in an element
* for XML output.
* @param text the element text body.
* @return a string so that it can be safely used as text in an element
* for XML output.
*/
public static String escape (String text)
{
final StringBuffer sb = new StringBuffer();
if (text != null)
{
char c;
final int l = text.length();
for (int i = 0; i < l; i++)
{
c = text.charAt(i);
switch (c)
{
case '<':
sb.append("<");
break;
case '>': // only needed to avoid ]]>
sb.append(">");
break;
case '&':
sb.append("&");
break;
default :
if (c > Byte.MAX_VALUE)
{
sb.append("&#x");
sb.append(Integer.toHexString(c));
sb.append(';');
}
else
{
sb.append(c);
}
}
}
}
return sb.toString();
}
/**
* Simple xml formatter.
* This code might fail for several input. In this case the
* original input is returned.
* @param org the input to be formated.
* @return the input in xml formated (human readable) form or the
* input string.
*/
public static String formatXml (String org)
{
String result = org;
try
{
final String in = org.trim();
if (in.charAt(0) == '<') // && sb.charAt(1) == '?')
{
final StringBuffer sb = new StringBuffer();
boolean nestedTag = false;
int indent = 0;
for (int t = 0; t < in.length(); t++)
{
char c = in.charAt(t);
switch (c)
{
case '<':
t++;
c = in.charAt(t);
switch (c)
{
case '/':
if (!nestedTag)
{
indent -= INDENT;
sb.append("</");
}
else
{
sb.append('\n');
indent -= INDENT;
indent(indent, sb);
sb.append("</");
}
nestedTag = true;
break;
case '?':
case '!':
if (t != 1)
{
sb.append('\n');
}
sb.append('<');
sb.append(c);
break;
default:
nestedTag = false;
if (sb.length() > 0)
{
sb.append('\n');
}
indent(indent, sb);
sb.append('<');
sb.append(c);
indent += INDENT;
break;
}
break;
case '/':
sb.append(c);
if (in.charAt(t + 1) == '>')
{
indent -= INDENT;
nestedTag = true;
}
break;
case '\n':
case '\r':
break;
case '>':
default:
sb.append(c);
break;
}
}
result = sb.toString();
}
}
catch (Exception ex)
{
result = org;
// CHECKME: Nicer exception handling no formated output...
}
return result;
}
/**
* Creae a stream result based on a File.
* Other than the default implementation not only the File is used to
* initialize the result, but also a Stream is opened and initialized.
* This works around an issue with whitespaces in the pathname which
* otherwise would lead to a file not found exception
* <pre>
* Error during transformation: javax.xml.transform.TransformerException: java.io.FileNotFoundException: ...%20...
* at org.apache.xalan.transformer.TransformerImpl.createSerializationHandler(TransformerImpl.java:1218)
* at org.apache.xalan.transformer.TransformerImpl.createSerializationHandler(TransformerImpl.java:1060)
* at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1268)
* at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1251)
* ....
* </pre>.
* The caller must ensure that the created outputstream is closed.
* @param outFile the file to be used in the stream result.
* @return a new StreamResult piontint to the given File.
* @throws IOException in case of an issue while creating the stream.
*/
public static StreamResult createStreamResult(File outFile)
throws IOException
{
final StreamResult result = new StreamResult(outFile);
// set the stream directly to avoid issues with blanks in the
// filename.
result.setOutputStream(new FileOutputStream(outFile));
return result;
}
private static void indent (final int i, StringBuffer b)
{
if (i > SPACES.length())
{
b.append(SPACES);
indent(i - SPACES.length(), b);
}
else
{
b.append(SPACES.substring(0, i));
}
}
}