org.mobicents.servlet.sip.address.RFC2396UrlDecoder Maven / Gradle / Ivy
/*
* JBoss, Home of Professional Open Source
* Copyright 2011, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* 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.
*
* This software 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.mobicents.servlet.sip.address;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.util.BitSet;
import org.apache.log4j.Logger;
/**
* Copied from Apache Excalibur project.
* Source code available at http://www.google.com/codesearch?hl=en&q=+excalibur+decodePath+show:sK_gDY0W5Rw:OTjCHAiSuF0:th3BdHtpX20&sa=N&cd=1&ct=rc&cs_p=http://apache.edgescape.com/excalibur/excalibur-sourceresolve/source/excalibur-sourceresolve-1.1-src.zip&cs_f=excalibur-sourceresolve-1.1/src/java/org/apache/excalibur/source/SourceUtil.java
* @author Jean Deruelle
*
*/
public class RFC2396UrlDecoder {
private static final String UTF_8 = "UTF-8";
static final BitSet CHARACHTERS_DONT_NEED_ECNODING;
static final int CHARACTER_CASE_DIFF = ('a' - 'A');
private final static Logger logger = Logger.getLogger(RFC2396UrlDecoder.class.getCanonicalName());
/** Initialize the BitSet */
static {
CHARACHTERS_DONT_NEED_ECNODING = new BitSet(256);
int i;
for (i = 'a'; i <= 'z'; i++) {
CHARACHTERS_DONT_NEED_ECNODING.set(i);
}
for (i = 'A'; i <= 'Z'; i++) {
CHARACHTERS_DONT_NEED_ECNODING.set(i);
}
for (i = '0'; i <= '9'; i++) {
CHARACHTERS_DONT_NEED_ECNODING.set(i);
}
CHARACHTERS_DONT_NEED_ECNODING.set('-');
CHARACHTERS_DONT_NEED_ECNODING.set('_');
CHARACHTERS_DONT_NEED_ECNODING.set('.');
CHARACHTERS_DONT_NEED_ECNODING.set('*');
CHARACHTERS_DONT_NEED_ECNODING.set('"');
}
/**
* Translates a string into x-www-form-urlencoded format.
*
* @param s String to be translated.
* @return the translated String.
*/
public static String encode(String s) {
final StringBuffer out = new StringBuffer(s.length());
final ByteArrayOutputStream buf = new ByteArrayOutputStream(32);
final OutputStreamWriter writer = new OutputStreamWriter(buf);
for (int i = 0; i < s.length(); i++) {
int c = s.charAt(i);
if (CHARACHTERS_DONT_NEED_ECNODING.get(c)) {
out.append((char) c);
} else {
try {
writer.write(c);
writer.flush();
} catch (IOException e) {
buf.reset();
continue;
}
byte[] ba = buf.toByteArray();
for (int j = 0; j < ba.length; j++) {
out.append('%');
char ch = Character.forDigit((ba[j] >> 4) & 0xF, 16);
// converting to use uppercase letter as part of
// the hex value if ch is a letter.
if (Character.isLetter(ch)) {
ch -= CHARACTER_CASE_DIFF;
}
out.append(ch);
ch = Character.forDigit(ba[j] & 0xF, 16);
if (Character.isLetter(ch)) {
ch -= CHARACTER_CASE_DIFF;
}
out.append(ch);
}
buf.reset();
}
}
return out.toString();
}
/**
* Decode a path.
*
* Interprets %XX (where XX is hexadecimal number) as UTF-8 encoded bytes.
*
The validity of the input path is not checked (i.e. characters that
* were not encoded will not be reported as errors).
*
This method differs from URLDecoder.decode in that it always uses UTF-8
* (while URLDecoder uses the platform default encoding, often ISO-8859-1),
* and doesn't translate + characters to spaces.
*
* @param uri the path to decode
* @return the decoded path
*/
public static String decode(String uri) {
if(logger.isDebugEnabled()) {
logger.debug("uri to decode " + uri);
}
if(uri == null) {
// fix by Hauke D. Issue 410
// throw new NullPointerException("uri cannot be null !");
return null;
}
StringBuffer translatedUri = new StringBuffer(uri.length());
byte[] encodedchars = new byte[uri.length() / 3];
int i = 0;
int length = uri.length();
int encodedcharsLength = 0;
while (i < length) {
if (uri.charAt(i) == '%') {
//we must process all consecutive %-encoded characters in one go, because they represent
//an UTF-8 encoded string, and in UTF-8 one character can be encoded as multiple bytes
while (i < length && uri.charAt(i) == '%') {
if (i + 2 < length) {
try {
byte x = (byte)Integer.parseInt(uri.substring(i + 1, i + 3), 16);
encodedchars[encodedcharsLength] = x;
} catch (NumberFormatException e) {
// do not throw exception, a % could be part of a IPv6 address and still be valid
// throw new IllegalArgumentException("Illegal hex characters in pattern %" + uri.substring(i + 1, i + 3));
}
encodedcharsLength++;
i += 3;
} else {
// do not throw exception, a % could be part of a IPv6 address and still be valid
// throw new IllegalArgumentException("% character should be followed by 2 hexadecimal characters.");
}
}
try {
String translatedPart = new String(encodedchars, 0, encodedcharsLength, UTF_8);
translatedUri.append(translatedPart);
} catch (UnsupportedEncodingException e) {
//the situation that UTF-8 is not supported is quite theoretical, so throw a runtime exception
throw new IllegalArgumentException("Problem in decodePath: UTF-8 encoding not supported.");
}
encodedcharsLength = 0;
} else {
//a normal character
translatedUri.append(uri.charAt(i));
i++;
}
}
if(logger.isDebugEnabled()) {
logger.debug("decoded uri " + translatedUri);
}
return translatedUri.toString();
}
}