| /* |
| * Copyright (c) 1995, 2004, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package sun.misc; |
| |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.io.PrintStream; |
| import java.io.IOException; |
| |
| /** |
| * This class implements a Berkeley uu character encoder. This encoder |
| * was made famous by uuencode program. |
| * |
| * The basic character coding is algorithmic, taking 6 bits of binary |
| * data and adding it to an ASCII ' ' (space) character. This converts |
| * these six bits into a printable representation. Note that it depends |
| * on the ASCII character encoding standard for english. Groups of three |
| * bytes are converted into 4 characters by treating the three bytes |
| * a four 6 bit groups, group 1 is byte 1's most significant six bits, |
| * group 2 is byte 1's least significant two bits plus byte 2's four |
| * most significant bits. etc. |
| * |
| * In this encoding, the buffer prefix is: |
| * <pre> |
| * begin [mode] [filename] |
| * </pre> |
| * |
| * This is followed by one or more lines of the form: |
| * <pre> |
| * (len)(data)(data)(data) ... |
| * </pre> |
| * where (len) is the number of bytes on this line. Note that groupings |
| * are always four characters, even if length is not a multiple of three |
| * bytes. When less than three characters are encoded, the values of the |
| * last remaining bytes is undefined and should be ignored. |
| * |
| * The last line of data in a uuencoded file is represented by a single |
| * space character. This is translated by the decoding engine to a line |
| * length of zero. This is immediately followed by a line which contains |
| * the word 'end[newline]' |
| * |
| * @author Chuck McManis |
| * @see CharacterEncoder |
| * @see UUDecoder |
| */ |
| public class UUEncoder extends CharacterEncoder { |
| |
| /** |
| * This name is stored in the begin line. |
| */ |
| private String bufferName; |
| |
| /** |
| * Represents UNIX(tm) mode bits. Generally three octal digits representing |
| * read, write, and execute permission of the owner, group owner, and |
| * others. They should be interpreted as the bit groups: |
| * (owner) (group) (others) |
| * rwx rwx rwx (r = read, w = write, x = execute) |
| * |
| * By default these are set to 644 (UNIX rw-r--r-- permissions). |
| */ |
| private int mode; |
| |
| |
| /** |
| * Default - buffer begin line will be: |
| * <pre> |
| * begin 644 encoder.buf |
| * </pre> |
| */ |
| public UUEncoder() { |
| bufferName = "encoder.buf"; |
| mode = 644; |
| } |
| |
| /** |
| * Specifies a name for the encoded buffer, begin line will be: |
| * <pre> |
| * begin 644 [FNAME] |
| * </pre> |
| */ |
| public UUEncoder(String fname) { |
| bufferName = fname; |
| mode = 644; |
| } |
| |
| /** |
| * Specifies a name and mode for the encoded buffer, begin line will be: |
| * <pre> |
| * begin [MODE] [FNAME] |
| * </pre> |
| */ |
| public UUEncoder(String fname, int newMode) { |
| bufferName = fname; |
| mode = newMode; |
| } |
| |
| /** number of bytes per atom in uuencoding is 3 */ |
| protected int bytesPerAtom() { |
| return (3); |
| } |
| |
| /** number of bytes per line in uuencoding is 45 */ |
| protected int bytesPerLine() { |
| return (45); |
| } |
| |
| /** |
| * encodeAtom - take three bytes and encodes them into 4 characters |
| * If len is less than 3 then remaining bytes are filled with '1'. |
| * This insures that the last line won't end in spaces and potentiallly |
| * be truncated. |
| */ |
| protected void encodeAtom(OutputStream outStream, byte data[], int offset, int len) |
| throws IOException { |
| byte a, b = 1, c = 1; |
| int c1, c2, c3, c4; |
| |
| a = data[offset]; |
| if (len > 1) { |
| b = data[offset+1]; |
| } |
| if (len > 2) { |
| c = data[offset+2]; |
| } |
| |
| c1 = (a >>> 2) & 0x3f; |
| c2 = ((a << 4) & 0x30) | ((b >>> 4) & 0xf); |
| c3 = ((b << 2) & 0x3c) | ((c >>> 6) & 0x3); |
| c4 = c & 0x3f; |
| outStream.write(c1 + ' '); |
| outStream.write(c2 + ' '); |
| outStream.write(c3 + ' '); |
| outStream.write(c4 + ' '); |
| return; |
| } |
| |
| /** |
| * Encode the line prefix which consists of the single character. The |
| * lenght is added to the value of ' ' (32 decimal) and printed. |
| */ |
| protected void encodeLinePrefix(OutputStream outStream, int length) |
| throws IOException { |
| outStream.write((length & 0x3f) + ' '); |
| } |
| |
| |
| /** |
| * The line suffix for uuencoded files is simply a new line. |
| */ |
| protected void encodeLineSuffix(OutputStream outStream) throws IOException { |
| pStream.println(); |
| } |
| |
| /** |
| * encodeBufferPrefix writes the begin line to the output stream. |
| */ |
| protected void encodeBufferPrefix(OutputStream a) throws IOException { |
| super.pStream = new PrintStream(a); |
| super.pStream.print("begin "+mode+" "); |
| if (bufferName != null) { |
| super.pStream.println(bufferName); |
| } else { |
| super.pStream.println("encoder.bin"); |
| } |
| super.pStream.flush(); |
| } |
| |
| /** |
| * encodeBufferSuffix writes the single line containing space (' ') and |
| * the line containing the word 'end' to the output stream. |
| */ |
| protected void encodeBufferSuffix(OutputStream a) throws IOException { |
| super.pStream.println(" \nend"); |
| super.pStream.flush(); |
| } |
| |
| } |