Mega Code Archive
QP Decoder Stream
<![CDATA[
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
/*
* @(#)QPDecoderStream.java 1.11 07/05/04
*/
import java.io.*;
/**
* This class implements a QP Decoder. It is implemented as
* a FilterInputStream, so one can just wrap this class around
* any input stream and read bytes from this filter. The decoding
* is done as the bytes are read out.
*
* @author John Mani
*/
public class QPDecoderStream extends FilterInputStream {
protected byte[] ba = new byte[2];
protected int spaces = 0;
/**
* Create a Quoted Printable decoder that decodes the specified
* input stream.
* @param in the input stream
*/
public QPDecoderStream(InputStream in) {
super(new PushbackInputStream(in, 2)); // pushback of size=2
}
/**
* Read the next decoded byte from this input stream. The byte
* is returned as an <code>int</code> in the range <code>0</code>
* to <code>255</code>. If no byte is available because the end of
* the stream has been reached, the value <code>-1</code> is returned.
* This method blocks until input data is available, the end of the
* stream is detected, or an exception is thrown.
*
* @return the next byte of data, or <code>-1</code> if the end of the
* stream is reached.
* @exception IOException if an I/O error occurs.
*/
public int read() throws IOException {
if (spaces > 0) {
// We have cached space characters, return one
spaces--;
return ' ';
}
int c = in.read();
if (c == ' ') {
// Got space, keep reading till we get a non-space char
while ((c = in.read()) == ' ')
spaces++;
if (c == '\r' || c == '\n' || c == -1)
// If the non-space char is CR/LF/EOF, the spaces we got
// so far is junk introduced during transport. Junk 'em.
spaces = 0;
else {
// The non-space char is NOT CR/LF, the spaces are valid.
((PushbackInputStream)in).unread(c);
c = ' ';
}
return c; // return either <SPACE> or <CR/LF>
}
else if (c == '=') {
// QP Encoded atom. Decode the next two bytes
int a = in.read();
if (a == '\n') {
/* Hmm ... not really confirming QP encoding, but lets
* allow this as a LF terminated encoded line .. and
* consider this a soft linebreak and recurse to fetch
* the next char.
*/
return read();
} else if (a == '\r') {
// Expecting LF. This forms a soft linebreak to be ignored.
int b = in.read();
if (b != '\n')
/* Not really confirming QP encoding, but
* lets allow this as well.
*/
((PushbackInputStream)in).unread(b);
return read();
} else if (a == -1) {
// Not valid QP encoding, but we be nice and tolerant here !
return -1;
} else {
ba[0] = (byte)a;
ba[1] = (byte)in.read();
try {
return ASCIIUtility.parseInt(ba, 0, 2, 16);
} catch (NumberFormatException nex) {
/*
System.err.println(
"Illegal characters in QP encoded stream: " +
ASCIIUtility.toString(ba, 0, 2)
);
*/
((PushbackInputStream)in).unread(ba);
return c;
}
}
}
return c;
}
/**
* Reads up to <code>len</code> decoded bytes of data from this input stream
* into an array of bytes. This method blocks until some input is
* available.
* <p>
*
* @param buf the buffer into which the data is read.
* @param off the start offset of the data.
* @param len the maximum number of bytes read.
* @return the total number of bytes read into the buffer, or
* <code>-1</code> if there is no more data because the end of
* the stream has been reached.
* @exception IOException if an I/O error occurs.
*/
public int read(byte[] buf, int off, int len) throws IOException {
int i, c;
for (i = 0; i < len; i++) {
if ((c = read()) == -1) {
if (i == 0) // At end of stream, so we should
i = -1; // return -1 , NOT 0.
break;
}
buf[off+i] = (byte)c;
}
return i;
}
/**
* Tests if this input stream supports marks. Currently this class
* does not support marks
*/
public boolean markSupported() {
return false;
}
/**
* Returns the number of bytes that can be read from this input
* stream without blocking. The QP algorithm does not permit
* a priori knowledge of the number of bytes after decoding, so
* this method just invokes the <code>available</code> method
* of the original input stream.
*/
public int available() throws IOException {
// This is bogus ! We don't really know how much
// bytes are available *after* decoding
return in.available();
}
/**** begin TEST program
public static void main(String argv[]) throws Exception {
FileInputStream infile = new FileInputStream(argv[0]);
QPDecoderStream decoder = new QPDecoderStream(infile);
int c;
while ((c = decoder.read()) != -1)
System.out.print((char)c);
System.out.println();
}
*** end TEST program ****/
}
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
/*
* @(#)ASCIIUtility.java 1.11 07/05/04
*/
class ASCIIUtility {
// Private constructor so that this class is not instantiated
private ASCIIUtility() { }
/**
* Convert the bytes within the specified range of the given byte
* array into a signed integer in the given radix . The range extends
* from <code>start</code> till, but not including <code>end</code>. <p>
*
* Based on java.lang.Integer.parseInt()
*/
public static int parseInt(byte[] b, int start, int end, int radix)
throws NumberFormatException {
if (b == null)
throw new NumberFormatException("null");
int result = 0;
boolean negative = false;
int i = start;
int limit;
int multmin;
int digit;
if (end > start) {
if (b[i] == '-') {
negative = true;
limit = Integer.MIN_VALUE;
i++;
} else {
limit = -Integer.MAX_VALUE;
}
multmin = limit / radix;
if (i < end) {
digit = Character.digit((char)b[i++], radix);
if (digit < 0) {
throw new NumberFormatException(
"illegal number: " + toString(b, start, end)
);
} else {
result = -digit;
}
}
while (i < end) {
// Accumulating negatively avoids surprises near MAX_VALUE
digit = Character.digit((char)b[i++], radix);
if (digit < 0) {
throw new NumberFormatException("illegal number");
}
if (result < multmin) {
throw new NumberFormatException("illegal number");
}
result *= radix;
if (result < limit + digit) {
throw new NumberFormatException("illegal number");
}
result -= digit;
}
} else {
throw new NumberFormatException("illegal number");
}
if (negative) {
if (i > start + 1) {
return result;
} else { /* Only got "-" */
throw new NumberFormatException("illegal number");
}
} else {
return -result;
}
}
/**
* Convert the bytes within the specified range of the given byte
* array into a signed integer . The range extends from
* <code>start</code> till, but not including <code>end</code>. <p>
*/
public static int parseInt(byte[] b, int start, int end)
throws NumberFormatException {
return parseInt(b, start, end, 10);
}
/**
* Convert the bytes within the specified range of the given byte
* array into a signed long in the given radix . The range extends
* from <code>start</code> till, but not including <code>end</code>. <p>
*
* Based on java.lang.Long.parseLong()
*/
public static long parseLong(byte[] b, int start, int end, int radix)
throws NumberFormatException {
if (b == null)
throw new NumberFormatException("null");
long result = 0;
boolean negative = false;
int i = start;
long limit;
long multmin;
int digit;
if (end > start) {
if (b[i] == '-') {
negative = true;
limit = Long.MIN_VALUE;
i++;
} else {
limit = -Long.MAX_VALUE;
}
multmin = limit / radix;
if (i < end) {
digit = Character.digit((char)b[i++], radix);
if (digit < 0) {
throw new NumberFormatException(
"illegal number: " + toString(b, start, end)
);
} else {
result = -digit;
}
}
while (i < end) {
// Accumulating negatively avoids surprises near MAX_VALUE
digit = Character.digit((char)b[i++], radix);
if (digit < 0) {
throw new NumberFormatException("illegal number");
}
if (result < multmin) {
throw new NumberFormatException("illegal number");
}
result *= radix;
if (result < limit + digit) {
throw new NumberFormatException("illegal number");
}
result -= digit;
}
} else {
throw new NumberFormatException("illegal number");
}
if (negative) {
if (i > start + 1) {
return result;
} else { /* Only got "-" */
throw new NumberFormatException("illegal number");
}
} else {
return -result;
}
}
/**
* Convert the bytes within the specified range of the given byte
* array into a signed long . The range extends from
* <code>start</code> till, but not including <code>end</code>. <p>
*/
public static long parseLong(byte[] b, int start, int end)
throws NumberFormatException {
return parseLong(b, start, end, 10);
}
/**
* Convert the bytes within the specified range of the given byte
* array into a String. The range extends from <code>start</code>
* till, but not including <code>end</code>. <p>
*/
public static String toString(byte[] b, int start, int end) {
int size = end - start;
char[] theChars = new char[size];
for (int i = 0, j = start; i < size; )
theChars[i++] = (char)(b[j++]&0xff);
return new String(theChars);
}
public static String toString(ByteArrayInputStream is) {
int size = is.available();
char[] theChars = new char[size];
byte[] bytes = new byte[size];
is.read(bytes, 0, size);
for (int i = 0; i < size;)
theChars[i] = (char)(bytes[i++]&0xff);
return new String(theChars);
}
public static byte[] getBytes(String s) {
char [] chars= s.toCharArray();
int size = chars.length;
byte[] bytes = new byte[size];
for (int i = 0; i < size;)
bytes[i] = (byte) chars[i++];
return bytes;
}
public static byte[] getBytes(InputStream is) throws IOException {
int len;
int size = 1024;
byte [] buf;
if (is instanceof ByteArrayInputStream) {
size = is.available();
buf = new byte[size];
len = is.read(buf, 0, size);
}
else {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
buf = new byte[size];
while ((len = is.read(buf, 0, size)) != -1)
bos.write(buf, 0, len);
buf = bos.toByteArray();
}
return buf;
}
}
]]>