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package zte.util;
import java.io.*; // needed only for main() method.
/**
* 将字符串用64位加密算法加密
* title: 销售自动化软件
* description: 实现销售人员能够将销售过程通过一个软件就能管理起来。同时相互之间能够共享信息。
* 兼容以前的act,outlook软件。
* 与office软件集成。
* copyright: copyright (c) 2001
* company: tcl企业软件有限责任公司
* @author tony.郑
* @date 17 march 2000
* @version 1.0
*/
//////////////////////license & copyright header/////////////////////////
// //
// base64 – encode/decode data using the base64 encoding scheme //
// //
// copyright (c) 1998 by kevin kelley //
// //
// this library 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 library 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 library; if not, write to the free software //
// foundation, inc., 59 temple place – suite 330, boston, ma //
// 02111-1307, usa, or contact the author: //
// //
// kevin kelley <kelley@ruralnet.net> – 30718 rd. 28, la junta, co, //
// 81050 usa. //
// //
////////////////////end license & copyright header///////////////////////
import java.io.*; // needed only for main() method.
/**
* provides encoding of raw bytes to base64-encoded characters, and
* decoding of base64 characters to raw bytes.
* 用于加密算法，64位加密软件
* @author kevin kelley (kelley@ruralnet.net)
* @version 1.3
* @date 06 august 1998
* @modified 14 february 2000
* @modified 22 september 2000
*/
public class base64 {
/**
* returns an array of base64-encoded characters to represent the
* passed data array.
*
* @param data the array of bytes to encode
* @return base64-coded character array.
*/
static public char[] encode(byte[] data)
{
char[] out = new char[((data.length + 2) / 3) * 4];
//
// 3 bytes encode to 4 chars. output is always an even
// multiple of 4 characters.
//
for (int i=0, index=0; i<data.length; i+=3, index+=4) {
boolean quad = false;
boolean trip = false;
int val = (0xff & (int) data[i]);
val <<= 8;
if ((i+1) < data.length) {
val |= (0xff & (int) data[i+1]);
trip = true;
}
val <<= 8;
if ((i+2) < data.length) {
val |= (0xff & (int) data[i+2]);
quad = true;
}
out[index+3] = alphabet[(quad? (val & 0x3f): 64)];
val >>= 6;
out[index+2] = alphabet[(trip? (val & 0x3f): 64)];
val >>= 6;
out[index+1] = alphabet[val & 0x3f];
val >>= 6;
out[index+0] = alphabet[val & 0x3f];
}
return out;
}
/**
* decodes a base-64 encoded stream to recover the original
* data. white space before and after will be trimmed away,
* but no other manipulation of the input will be performed.
*
* as of version 1.2 this method will properly handle input
* containing junk characters (newlines and the like) rather
* than throwing an error. it does this by pre-parsing the
* input and generating from that a count of valid input
* characters.
**/
static public byte[] decode(char[] data)
{
// as our input could contain non-base64 data (newlines,
// whitespace of any sort, whatever) we must first adjust
// our count of usable data so that…
// (a) we dont misallocate the output array, and
// (b) think that we miscalculated our data length
// just because of extraneous throw-away junk
int templen = data.length;
for( int ix=0; ix<data.length; ix++ )
{
if( (data[ix] > 255) || codes[ data[ix] ] < 0 )
–templen; // ignore non-valid chars and padding
}
// calculate required length:
// — 3 bytes for every 4 valid base64 chars
// — plus 2 bytes if there are 3 extra base64 chars,
// or plus 1 byte if there are 2 extra.
int len = (templen / 4) * 3;
if ((templen % 4) == 3) len += 2;
if ((templen % 4) == 2) len += 1;
byte[] out = new byte[len];
int shift = 0; // # of excess bits stored in accum
int accum = 0; // excess bits
int index = 0;
// we now go through the entire array (not using the templen value)
for (int ix=0; ix<data.length; ix++)
{
int value = (data[ix]>255)? -1: codes[ data[ix] ];
if ( value >= 0 ) // skip over non-code
{
accum <<= 6; // bits shift up by 6 each time thru
shift += 6; // loop, with new bits being put in
accum |= value; // at the bottom.
if ( shift >= 8 ) // whenever there are 8 or more shifted in,
{
shift -= 8; // write them out (from the top, leaving any
out[index++] = // excess at the bottom for next iteration.
(byte) ((accum >> shift) & 0xff);
}
}
// we will also have skipped processing a padding null byte (=) here;
// these are used only for padding to an even length and do not legally
// occur as encoded data. for this reason we can ignore the fact that
// no index++ operation occurs in that special case: the out[] array is
// initialized to all-zero bytes to start with and that works to our
// advantage in this combination.
}
// if there is still something wrong we just have to throw up now!
if( index != out.length)
{
throw new error("miscalculated data length (wrote " + index + " instead of " + out.length + ")");
}
return out;
}
//
// code characters for values 0..63
//
static private char[] alphabet =
"abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789+/="
.tochararray();
//
// lookup table for converting base64 characters to value in range 0..63
//
static private byte[] codes = new byte[256];
static {
for (int i=0; i<256; i++) codes[i] = -1;
for (int i = a; i <= z; i++) codes[i] = (byte)( i – a);
for (int i = a; i <= z; i++) codes[i] = (byte)(26 + i – a);
for (int i = 0; i <= 9; i++) codes[i] = (byte)(52 + i – 0);
codes[+] = 62;
codes[/] = 63;
}
///////////////////////////////////////////////////
// remainder (main method and helper functions) is
// for testing purposes only, feel free to clip it.
///////////////////////////////////////////////////
public static void main(string[] args)
{
boolean decode = false;
if (args.length == 0) {
system.out.println("usage: java base64 [-d[ecode]] filename");
system.exit(0);
}
for (int i=0; i<args.length; i++) {
if ("-decode".equalsignorecase(args[i])) decode = true;
else if ("-d".equalsignorecase(args[i])) decode = true;
}
string filename = args[args.length-1];
file file = new file(filename);
if (!file.exists()) {
system.out.println("error: file " + filename + " doesnt exist!");
system.exit(0);
}
if (decode)
{
char[] encoded = readchars(file);
byte[] decoded = decode(encoded);
writebytes(file, decoded);
}
else
{
byte[] decoded = readbytes(file);
char[] encoded = encode(decoded);
writechars(file, encoded);
}
}
private static byte[] readbytes(file file)
{
bytearrayoutputstream baos = new bytearrayoutputstream();
try
{
inputstream fis = new fileinputstream(file);
inputstream is = new bufferedinputstream(fis);
int count = 0;
byte[] buf = new byte[16384];
while ((count=is.read(buf)) != -1) {
if (count > 0) baos.write(buf, 0, count);
}
is.close();
}
catch (exception e) { e.printstacktrace(); }
return baos.tobytearray();
}
private static char[] readchars(file file)
{
chararraywriter caw = new chararraywriter();
try
{
reader fr = new filereader(file);
reader in = new bufferedreader(fr);
int count = 0;
char[] buf = new char[16384];
while ((count=in.read(buf)) != -1) {
if (count > 0) caw.write(buf, 0, count);
}
in.close();
}
catch (exception e) { e.printstacktrace(); }
return caw.tochararray();
}
private static void writebytes(file file, byte[] data) {
try {
outputstream fos = new fileoutputstream(file);
outputstream os = new bufferedoutputstream(fos);
os.write(data);
os.close();
}
catch (exception e) { e.printstacktrace(); }
}
private static void writechars(file file, char[] data) {
try {
writer fos = new filewriter(file);
writer os = new bufferedwriter(fos);
os.write(data);
os.close();
}
catch (exception e) { e.printstacktrace(); }
}
///////////////////////////////////////////////////
// end of test code.
///////////////////////////////////////////////////
}
