/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
* ITS 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.xml.serializer;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.MalformedURLException;
import java.util.BitSet;
import java.util.Hashtable;
import java.util.PropertyResourceBundle;
import java.util.ResourceBundle;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.Enumeration;
import org.apache.xml.res.XMLErrorResources;
import org.apache.xml.res.XMLMessages;
import org.apache.xml.utils.CharKey;
import org.apache.xml.utils.SystemIDResolver;
import org.apache.xml.utils.SystemIDResolver;
/**
* This class provides services that tell if a character should have
* special treatement, such as entity reference substitution or normalization
* of a newline character. It also provides character to entity reference
* lookup.
*
* DEVELOPERS: See Known Issue in the constructor.
*/
public class CharInfo
{
/** Bit map that tells if a given character should have special treatment. */
BitSet m_specialsMap = new BitSet(65535);
/** Lookup table for characters to entity references. */
private Hashtable m_charToEntityRef = new Hashtable();
/**
* The name of the HTML entities file.
* If specified, the file will be resource loaded with the default class loader.
*/
public static String HTML_ENTITIES_RESOURCE = "org.apache.xml.serializer.HTMLEntities";
/**
* The name of the XML entities file.
* If specified, the file will be resource loaded with the default class loader.
*/
public static String XML_ENTITIES_RESOURCE = "org.apache.xml.serializer.XMLEntities";
/** The linefeed character, which the parser should always normalize. */
public static final char S_LINEFEED = 0x0A;
/** The carriage return character, which the parser should always normalize. */
public static char S_CARRIAGERETURN = 0x0D;
/**
* Constructor that reads in a resource file that describes the mapping of
* characters to entity references.
*
* Resource files must be encoded in UTF-8 and can either be properties
* files with a .properties extension assumed. Alternatively, they can
* have the following form, with no particular extension assumed:
*
* <pre>
* # First char # is a comment
* Entity numericValue
* quot 34
* amp 38
* </pre>
*
* @param entitiesResource Name of properties or resource file that should
* be loaded, which describes that mapping of characters to entity
* references.
*/
public CharInfo(String entitiesResource)
{
PropertyResourceBundle entities;
InputStream is = null;
BufferedReader reader = null;
int index;
String name;
String value;
int code;
String line;
// Make various attempts to interpret the parameter as a properties
// file or resource file, as follows:
//
// 1) attempt to load .properties file using ResourceBundle
// 2) try using the class loader to find the specified file a resource
// file
// 3) try treating the resource a URI
entities = loadEntitiesResource(entitiesResource);
if (null != entities) {
Enumeration enum = entities.getKeys();
while (enum.hasMoreElements()){
name = (String) enum.nextElement();
value = entities.getString(name);
code = Integer.parseInt(value);
defineEntity(name, (char) code);
}
m_specialsMap.set(S_LINEFEED);
m_specialsMap.set(S_CARRIAGERETURN);
} else {
// Load user specified resource file by using URL loading, it
// requires a valid URI as parameter;
try {
try {
// Maintenance note: we should evaluate replacing getting
// the ClassLoader with
// javax.xml.transform.FactoryFinder.findClassLoader()
// or similar code
ClassLoader cl = CharInfo.class.getClassLoader();
if (cl == null) {
is = ClassLoader.getSystemResourceAsStream(
entitiesResource);
} else {
is = cl.getResourceAsStream(entitiesResource);
}
} catch (Exception e) { }
if (is == null) {
is = CharInfo.class.getResourceAsStream(entitiesResource);
}
if (is == null) {
URL url = new URL(entitiesResource);
is = url.openStream();
}
if (is == null) {
throw new RuntimeException(
XMLMessages.createXMLMessage(
XMLErrorResources.ER_RESOURCE_COULD_NOT_FIND,
new Object[] {entitiesResource, entitiesResource}));
}
// Fix Bugzilla#4000: force reading in UTF-8
// This creates the de facto standard that Xalan's resource
// files must be encoded in UTF-8. This should work in all
// JVMs.
//
// %REVIEW% KNOWN ISSUE: IT FAILS IN MICROSOFT VJ++, which
// didn't implement the UTF-8 encoding. Theoretically, we should
// simply let it fail in that case, since the JVM is obviously
// broken if it doesn't support such a basic standard. But
// since there are still some users attempting to use VJ++ for
// development, we have dropped in a fallback which makes a
// second attempt using the platform's default encoding. In VJ++
// this is apparently ASCII, which is subset of UTF-8... and
// since the strings we'll be reading here are also primarily
// limited to the 7-bit ASCII range (at least, in English
// versions of Xalan), this should work well enough to keep us
// on the air until we're ready to officially decommit from
// VJ++.
try {
reader = new BufferedReader(new InputStreamReader(is,
"UTF-8"));
} catch (java.io.UnsupportedEncodingException e) {
reader = new BufferedReader(new InputStreamReader(is));
}
line = reader.readLine();
while (line != null) {
if (line.length() == 0 || line.charAt(0) == '#') {
line = reader.readLine();
continue;
}
index = line.indexOf(' ');
if (index > 1) {
name = line.substring(0, index);
++index;
if (index < line.length()) {
value = line.substring(index);
index = value.indexOf(' ');
if (index > 0) {
value = value.substring(0, index);
}
code = Integer.parseInt(value);
defineEntity(name, (char) code);
}
}
line = reader.readLine();
}
is.close();
m_specialsMap.set(S_LINEFEED);
m_specialsMap.set(S_CARRIAGERETURN);
} catch (Exception except) {
throw new RuntimeException(
XMLMessages.createXMLMessage(
XMLErrorResources.ER_RESOURCE_COULD_NOT_LOAD,
new Object[] { entitiesResource,
except.toString(),
entitiesResource,
except.toString()}));
} finally {
if (is != null) {
try {
is.close();
} catch (Exception except) { }
}
}
}
}
/**
* Defines a new character reference. The reference's name and value are
* supplied. Nothing happens if the character reference is already defined.
* <p>Unlike internal entities, character references are a string to single
* character mapping. They are used to map non-ASCII characters both on
* parsing and printing, primarily for HTML documents. '<amp;' is an
* example of a character reference.</p>
*
* @param name The entity's name
* @param value The entity's value
*/
protected void defineEntity(String name, char value)
{
CharKey character = new CharKey(value);
m_charToEntityRef.put(character, name);
m_specialsMap.set(value);
}
private CharKey m_charKey = new CharKey();
/**
* Resolve a character to an entity reference name.
*
* This is reusing a stored key object, in an effort to avoid
* heap activity. Unfortunately, that introduces a threading risk.
* Simplest fix for now is to make it a synchronized method, or to give
* up the reuse; I see very little performance difference between them.
* Long-term solution would be to replace the hashtable with a sparse array
* keyed directly from the character's integer value; see DTM's
* string pool for a related solution.
*
* @param value character value that should be resolved to a name.
*
* @return name of character entity, or null if not found.
*/
synchronized public String getEntityNameForChar(char value)
{
// CharKey m_charKey = new CharKey(); //Alternative to synchronized
m_charKey.setChar(value);
return (String) m_charToEntityRef.get(m_charKey);
}
/**
* Tell if the character argument should have special treatment.
*
* @param value character value.
*
* @return true if the character should have any special treatment, such as
* when writing out attribute values, or entity references.
*/
public boolean isSpecial(char value)
{
return m_specialsMap.get(value);
}
/** Table of user-specified char infos. */
private static Hashtable m_getCharInfo_cache = null;
/**
* Factory that reads in a resource file that describes the mapping of
* characters to entity references.
*
* Resource files must be encoded in UTF-8 and have a format like:
* <pre>
* # First char # is a comment
* Entity numericValue
* quot 34
* amp 38
* </pre>
* (Note: Why don't we just switch to .properties files? Oct-01 -sc)
*
* @param entitiesResource Name of entities resource file that should
* be loaded, which describes that mapping of characters to entity references.
*/
public static CharInfo getCharInfo(String entitiesFileName)
{
CharInfo retobj = null;
if (null == m_getCharInfo_cache)
{
// synchronize on any object, just to have a lock while creating the cache.
synchronized (XML_ENTITIES_RESOURCE)
{
if (null == m_getCharInfo_cache) // secondary check
m_getCharInfo_cache = new Hashtable();
}
}
else
{
// the cache already exists, so lets try to find it.
retobj = (CharInfo) m_getCharInfo_cache.get(entitiesFileName);
}
if (retobj == null)
{
// try to load it.
try
{
retobj = new CharInfo(entitiesFileName);
m_getCharInfo_cache.put(entitiesFileName, retobj);
}
catch (Exception e)
{
retobj = null;
}
}
if (null == retobj)
{
String absoluteEntitiesFileName;
if (entitiesFileName.indexOf(':') < 0)
{
absoluteEntitiesFileName =
SystemIDResolver.getAbsoluteURIFromRelative(
entitiesFileName);
}
else
{
try
{
absoluteEntitiesFileName =
SystemIDResolver.getAbsoluteURI(entitiesFileName, null);
}
catch (javax.xml.transform.TransformerException te)
{
throw new org.apache.xml.utils.WrappedRuntimeException(te);
}
}
retobj = new CharInfo(absoluteEntitiesFileName);
m_getCharInfo_cache.put(entitiesFileName, retobj);
}
return retobj;
}
//Load entity property files by using PropertyResourceBundle, cause of security issure for applets
private PropertyResourceBundle loadEntitiesResource(String baseName)
throws MissingResourceException
{
try
{
Locale locale = Locale.getDefault();
java.lang.ClassLoader loader = this.getClass().getClassLoader();
return (PropertyResourceBundle)PropertyResourceBundle.getBundle(baseName);
}
catch (MissingResourceException e)
{
return null;
}
}
}