Encode and decode integers, times, and internationalized strings to and from popular binary formats
/* encdec - encode and decode integers, times, and
* internationalized strings to and from popular binary formats
* http://www.ioplex.com/~miallen/encdec/
* Copyright (c) 2003 Michael B. Allen <mballen@erols.com>
*
* The GNU Library General Public License
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library 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
*/
import java.util.Date;
import java.io.IOException;
public class Encdec {
public static final long MILLISECONDS_BETWEEN_1970_AND_1601 = 11644473600000L;
public static final long SEC_BETWEEEN_1904_AND_1970 = 2082844800L;
public static final int TIME_1970_SEC_32BE = 1;
public static final int TIME_1970_SEC_32LE = 2;
public static final int TIME_1904_SEC_32BE = 3;
public static final int TIME_1904_SEC_32LE = 4;
public static final int TIME_1601_NANOS_64LE = 5;
public static final int TIME_1601_NANOS_64BE = 6;
public static final int TIME_1970_MILLIS_64BE = 7;
public static final int TIME_1970_MILLIS_64LE = 8;
/* Encode integers
*/
public static int enc_uint16be( short s, byte[] dst, int di ) {
dst[di++] = (byte)((s >> 8) & 0xFF);
dst[di] = (byte)(s & 0xFF);
return 2;
}
public static int enc_uint32be( int i, byte[] dst, int di ) {
dst[di++] = (byte)((i >> 24) & 0xFF);
dst[di++] = (byte)((i >> 16) & 0xFF);
dst[di++] = (byte)((i >> 8) & 0xFF);
dst[di] = (byte)(i & 0xFF);
return 4;
}
public static int enc_uint16le( short s, byte[] dst, int di )
{
dst[di++] = (byte)(s & 0xFF);
dst[di] = (byte)((s >> 8) & 0xFF);
return 2;
}
public static int enc_uint32le( int i, byte[] dst, int di )
{
dst[di++] = (byte)(i & 0xFF);
dst[di++] = (byte)((i >> 8) & 0xFF);
dst[di++] = (byte)((i >> 16) & 0xFF);
dst[di] = (byte)((i >> 24) & 0xFF);
return 4;
}
/* Decode integers
*/
public static short dec_uint16be( byte[] src, int si )
{
return (short)(((src[si] & 0xFF) << 8) | (src[si + 1] & 0xFF));
}
public static int dec_uint32be( byte[] src, int si )
{
return ((src[si] & 0xFF) << 24) | ((src[si + 1] & 0xFF) << 16) |
((src[si + 2] & 0xFF) << 8) | (src[si + 3] & 0xFF);
}
public static short dec_uint16le( byte[] src, int si )
{
return (short)((src[si] & 0xFF) | ((src[si + 1] & 0xFF) << 8));
}
public static int dec_uint32le( byte[] src, int si )
{
return (src[si] & 0xFF) | ((src[si + 1] & 0xFF) << 8) |
((src[si + 2] & 0xFF) << 16) | ((src[si + 3] & 0xFF) << 24);
}
/* Encode and decode 64 bit integers
*/
public static int enc_uint64be( long l, byte[] dst, int di )
{
enc_uint32be( (int)(l & 0xFFFFFFFFL), dst, di + 4 );
enc_uint32be( (int)(( l >> 32L ) & 0xFFFFFFFFL), dst, di );
return 8;
}
public static int enc_uint64le( long l, byte[] dst, int di )
{
enc_uint32le( (int)(l & 0xFFFFFFFFL), dst, di );
enc_uint32le( (int)(( l >> 32L ) & 0xFFFFFFFFL), dst, di + 4 );
return 8;
}
public static long dec_uint64be( byte[] src, int si )
{
long l;
l = dec_uint32be( src, si ) & 0xFFFFFFFFL;
l <<= 32L;
l |= dec_uint32be( src, si + 4 ) & 0xFFFFFFFFL;
return l;
}
public static long dec_uint64le( byte[] src, int si )
{
long l;
l = dec_uint32le( src, si + 4 ) & 0xFFFFFFFFL;
l <<= 32L;
l |= dec_uint32le( src, si ) & 0xFFFFFFFFL;
return l;
}
/* Encode floats
*/
public static int enc_floatle( float f, byte[] dst, int di )
{
return enc_uint32le( Float.floatToIntBits( f ), dst, di );
}
public static int enc_floatbe( float f, byte[] dst, int di )
{
return enc_uint32be( Float.floatToIntBits( f ), dst, di );
}
/* Decode floating point numbers
*/
public static float dec_floatle( byte[] src, int si )
{
return Float.intBitsToFloat( dec_uint32le( src, si ));
}
public static float dec_floatbe( byte[] src, int si )
{
return Float.intBitsToFloat( dec_uint32be( src, si ));
}
/* Encode and decode doubles
*/
public static int enc_doublele( double d, byte[] dst, int di )
{
return enc_uint64le( Double.doubleToLongBits( d ), dst, di );
}
public static int enc_doublebe( double d, byte[] dst, int di )
{
return enc_uint64be( Double.doubleToLongBits( d ), dst, di );
}
public static double dec_doublele( byte[] src, int si )
{
return Double.longBitsToDouble( dec_uint64le( src, si ));
}
public static double dec_doublebe( byte[] src, int si )
{
return Double.longBitsToDouble( dec_uint64be( src, si ));
}
/* Encode times
*/
public static int enc_time( Date date, byte[] dst, int di, int enc )
{
long t;
switch( enc ) {
case TIME_1970_SEC_32BE:
return enc_uint32be( (int)(date.getTime() / 1000L), dst, di );
case TIME_1970_SEC_32LE:
return enc_uint32le( (int)(date.getTime() / 1000L), dst, di );
case TIME_1904_SEC_32BE:
return enc_uint32be( (int)((date.getTime() / 1000L +
SEC_BETWEEEN_1904_AND_1970) & 0xFFFFFFFF), dst, di );
case TIME_1904_SEC_32LE:
return enc_uint32le( (int)((date.getTime() / 1000L +
SEC_BETWEEEN_1904_AND_1970) & 0xFFFFFFFF), dst, di );
case TIME_1601_NANOS_64BE:
t = (date.getTime() + MILLISECONDS_BETWEEN_1970_AND_1601) * 10000L;
return enc_uint64be( t, dst, di );
case TIME_1601_NANOS_64LE:
t = (date.getTime() + MILLISECONDS_BETWEEN_1970_AND_1601) * 10000L;
return enc_uint64le( t, dst, di );
case TIME_1970_MILLIS_64BE:
return enc_uint64be( date.getTime(), dst, di );
case TIME_1970_MILLIS_64LE:
return enc_uint64le( date.getTime(), dst, di );
default:
throw new IllegalArgumentException( "Unsupported time encoding" );
}
}
/* Decode times
*/
public static Date dec_time( byte[] src, int si, int enc )
{
long t;
switch( enc ) {
case TIME_1970_SEC_32BE:
return new Date( dec_uint32be( src, si ) * 1000L );
case TIME_1970_SEC_32LE:
return new Date( dec_uint32le( src, si ) * 1000L );
case TIME_1904_SEC_32BE:
return new Date((( dec_uint32be( src, si ) & 0xFFFFFFFFL) -
SEC_BETWEEEN_1904_AND_1970 ) * 1000L );
case TIME_1904_SEC_32LE:
return new Date((( dec_uint32le( src, si ) & 0xFFFFFFFFL) -
SEC_BETWEEEN_1904_AND_1970 ) * 1000L );
case TIME_1601_NANOS_64BE:
t = dec_uint64be( src, si );
return new Date( t / 10000L - MILLISECONDS_BETWEEN_1970_AND_1601);
case TIME_1601_NANOS_64LE:
t = dec_uint64le( src, si );
return new Date( t / 10000L - MILLISECONDS_BETWEEN_1970_AND_1601);
case TIME_1970_MILLIS_64BE:
return new Date( dec_uint64be( src, si ));
case TIME_1970_MILLIS_64LE:
return new Date( dec_uint64le( src, si ));
default:
throw new IllegalArgumentException( "Unsupported time encoding" );
}
}
public static int enc_utf8( String str, byte[] dst, int di, int dlim ) throws IOException {
int start = di, ch;
int strlen = str.length();
for( int i = 0; di < dlim && i < strlen; i++ ) {
ch = str.charAt( i );
if ((ch >= 0x0001) && (ch <= 0x007F)) {
dst[di++] = (byte)ch;
} else if (ch > 0x07FF) {
if((dlim - di) < 3 ) {
break;
}
dst[di++] = (byte)(0xE0 | ((ch >> 12) & 0x0F));
dst[di++] = (byte)(0x80 | ((ch >> 6) & 0x3F));
dst[di++] = (byte)(0x80 | ((ch >> 0) & 0x3F));
} else {
if((dlim - di) < 2 ) {
break;
}
dst[di++] = (byte)(0xC0 | ((ch >> 6) & 0x1F));
dst[di++] = (byte)(0x80 | ((ch >> 0) & 0x3F));
}
}
return di - start;
}
public static String dec_utf8( byte[] src, int si, int slim ) throws IOException {
char[] uni = new char[slim - si];
int ui, ch;
for( ui = 0; si < slim && (ch = src[si++] & 0xFF) != 0; ui++ ) {
if( ch < 0x80 ) {
uni[ui] = (char)ch;
} else if((ch & 0xE0) == 0xC0 ) {
if((slim - si) < 2 ) {
break;
}
uni[ui] = (char)((ch & 0x1F) << 6);
ch = src[si++] & 0xFF;
uni[ui] |= ch & 0x3F;
if ((ch & 0xC0) != 0x80 || uni[ui] < 0x80 ) {
throw new IOException( "Invalid UTF-8 sequence" );
}
} else if((ch & 0xF0) == 0xE0 ) {
if((slim - si) < 3 ) {
break;
}
uni[ui] = (char)((ch & 0x0F) << 12);
ch = src[si++] & 0xFF;
if ((ch & 0xC0) != 0x80 ) {
throw new IOException( "Invalid UTF-8 sequence" );
} else {
uni[ui] |= (ch & 0x3F) << 6;
ch = src[si++] & 0xFF;
uni[ui] |= ch & 0x3F;
if ((ch & 0xC0) != 0x80 || uni[ui] < 0x800) {
throw new IOException( "Invalid UTF-8 sequence" );
}
}
} else {
throw new IOException( "Unsupported UTF-8 sequence" );
}
}
return new String( uni, 0, ui );
}
public static String dec_ucs2le( byte[] src, int si, int slim, char[] buf ) throws IOException {
int bi;
for( bi = 0; (si + 1) < slim; bi++, si += 2 ) {
buf[bi] = (char)dec_uint16le( src, si );
if( buf[bi] == '\0' ) {
break;
}
}
return new String( buf, 0, bi );
}
}
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