QPEncoderStream.java Source code

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Here is the source code for QPEncoderStream.java

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/*
 * 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.
 */

/*
 * @(#)QPEncoderStream.java 1.8 07/05/04
 */

import java.io.*;

/**
 * This class implements a Quoted Printable Encoder. It is implemented as
 * a FilterOutputStream, so one can just wrap this class around
 * any output stream and write bytes into this filter. The Encoding
 * is done as the bytes are written out.
 * 
 * @author John Mani
 */

public class QPEncoderStream extends FilterOutputStream {
    private int count = 0; // number of bytes that have been output
    private int bytesPerLine; // number of bytes per line
    private boolean gotSpace = false;
    private boolean gotCR = false;

    /**
     * Create a QP encoder that encodes the specified input stream
     * @param out        the output stream
     * @param bytesPerLine  the number of bytes per line. The encoder
     *                   inserts a CRLF sequence after this many number
     *                   of bytes.
     */
    public QPEncoderStream(OutputStream out, int bytesPerLine) {
        super(out);
        // Subtract 1 to account for the '=' in the soft-return 
        // at the end of a line
        this.bytesPerLine = bytesPerLine - 1;
    }

    /**
     * Create a QP encoder that encodes the specified input stream.
     * Inserts the CRLF sequence after outputting 76 bytes.
     * @param out        the output stream
     */
    public QPEncoderStream(OutputStream out) {
        this(out, 76);
    }

    /**
     * Encodes <code>len</code> bytes from the specified
     * <code>byte</code> array starting at offset <code>off</code> to
     * this output stream.
     *
     * @param      b     the data.
     * @param      off   the start offset in the data.
     * @param      len   the number of bytes to write.
     * @exception  IOException  if an I/O error occurs.
     */
    public void write(byte[] b, int off, int len) throws IOException {
        for (int i = 0; i < len; i++)
            write(b[off + i]);
    }

    /**
     * Encodes <code>b.length</code> bytes to this output stream.
     * @param      b   the data to be written.
     * @exception  IOException  if an I/O error occurs.
     */
    public void write(byte[] b) throws IOException {
        write(b, 0, b.length);
    }

    /**
     * Encodes the specified <code>byte</code> to this output stream.
     * @param      c   the <code>byte</code>.
     * @exception  IOException  if an I/O error occurs.
     */
    public void write(int c) throws IOException {
        c = c & 0xff; // Turn off the MSB.
        if (gotSpace) { // previous character was <SPACE>
            if (c == '\r' || c == '\n')
                // if CR/LF, we need to encode the <SPACE> char
                output(' ', true);
            else // no encoding required, just output the char
                output(' ', false);
            gotSpace = false;
        }

        if (c == '\r') {
            gotCR = true;
            outputCRLF();
        } else {
            if (c == '\n') {
                if (gotCR)
                    // This is a CRLF sequence, we already output the 
                    // corresponding CRLF when we got the CR, so ignore this
                    ;
                else
                    outputCRLF();
            } else if (c == ' ') {
                gotSpace = true;
            } else if (c < 040 || c >= 0177 || c == '=')
                // Encoding required. 
                output(c, true);
            else // No encoding required
                output(c, false);
            // whatever it was, it wasn't a CR
            gotCR = false;
        }
    }

    /**
     * Flushes this output stream and forces any buffered output bytes
     * to be encoded out to the stream.
     * @exception  IOException  if an I/O error occurs.
     */
    public void flush() throws IOException {
        out.flush();
    }

    /**
     * Forces any buffered output bytes to be encoded out to the stream
     * and closes this output stream
     */
    public void close() throws IOException {
        out.close();
    }

    private void outputCRLF() throws IOException {
        out.write('\r');
        out.write('\n');
        count = 0;
    }

    // The encoding table
    private final static char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E',
            'F' };

    protected void output(int c, boolean encode) throws IOException {
        if (encode) {
            if ((count += 3) > bytesPerLine) {
                out.write('=');
                out.write('\r');
                out.write('\n');
                count = 3; // set the next line's length
            }
            out.write('=');
            out.write(hex[c >> 4]);
            out.write(hex[c & 0xf]);
        } else {
            if (++count > bytesPerLine) {
                out.write('=');
                out.write('\r');
                out.write('\n');
                count = 1; // set the next line's length
            }
            out.write(c);
        }
    }

    /**** begin TEST program ***
    public static void main(String argv[]) throws Exception {
    FileInputStream infile = new FileInputStream(argv[0]);
    QPEncoderStream encoder = new QPEncoderStream(System.out);
    int c;
        
    while ((c = infile.read()) != -1)
        encoder.write(c);
    encoder.close();
    }
    *** 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;
    }
}