- added base64 ordering methods

- added coding interface

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@1285 6c8d7289-2bf4-0310-a012-ef5d649a1542
pull/1/head
orbiter 19 years ago
parent 9086261476
commit 10a095d6b5

@ -48,7 +48,7 @@ package de.anomic.kelondro;
import java.util.Comparator;
public class kelondroBase64Order extends kelondroAbstractOrder implements kelondroOrder, Comparator {
public class kelondroBase64Order extends kelondroAbstractOrder implements kelondroOrder, kelondroCoding, Comparator {
public static final kelondroBase64Order standardCoder = new kelondroBase64Order(true);
public static final kelondroBase64Order enhancedCoder = new kelondroBase64Order(false);
@ -84,9 +84,7 @@ public class kelondroBase64Order extends kelondroAbstractOrder implements kelond
if (c >= max(length)) {
StringBuffer s = new StringBuffer(length);
s.setLength(length);
while (length > 0) {
s.setCharAt(--length, alpha[0]);
}
while (length > 0) s.setCharAt(--length, alpha[63]);
return s.toString();
} else {
return encodeLong(c, length);
@ -107,10 +105,7 @@ public class kelondroBase64Order extends kelondroAbstractOrder implements kelond
while (s.endsWith("="))
s = s.substring(0, s.length() - 1);
long c = 0;
for (int i = 0; i < s.length(); i++) {
c <<= 6;
c += ahpla[s.charAt(i)];
}
for (int i = 0; i < s.length(); i++) c = (c << 6) | ahpla[s.charAt(i)];
return c;
}
@ -118,10 +113,7 @@ public class kelondroBase64Order extends kelondroAbstractOrder implements kelond
// computes the maximum number that can be coded with a base64-encoded
// String of base len
long c = 0;
for (int i = 0; i < len; i++) {
c <<= 6;
c += 63;
}
for (int i = 0; i < len; i++) c = (c << 6) | 63;
return c;
}
@ -203,12 +195,35 @@ public class kelondroBase64Order extends kelondroAbstractOrder implements kelond
}
public long cardinal(byte[] key) {
// TODO Auto-generated method stub
return 0;
// returns a cardinal number in the range of 0 .. Long.MAX_VALUE
long c = 0;
int p = 0;
while ((p < 10) && (p < key.length)) c = (c << 6) | ahpla[key[p++]];
while (p++ < 10) c = (c << 6);
c = c << 3;
return c;
}
public int compare(byte[] a, byte[] b) {
// TODO Auto-generated method stub
int i = 0;
final int al = a.length;
final int bl = b.length;
final int len = (al > bl) ? bl : al;
while (i < len) {
if (ahpla[a[i]] > ahpla[b[i]])
return 1;
if (ahpla[a[i]] < ahpla[b[i]])
return -1;
// else the bytes are equal and it may go on yet undecided
i++;
}
// check if we have a zero-terminated equality
if ((i == al) && (i < bl) && (b[i] == 0)) return 0;
if ((i == bl) && (i < al) && (a[i] == 0)) return 0;
// no, decide by length
if (al > bl) return 1;
if (al < bl) return -1;
// no, they are equal
return 0;
}

@ -0,0 +1,63 @@
// kelondroCoder.java
// -----------------------
// part of The Kelondro Database
// (C) by Michael Peter Christen; mc@anomic.de
// first published on http://www.anomic.de
// Frankfurt, Germany, 2005
// created 04.01.2006
//
// $LastChangedDate: 2005-09-22 22:01:26 +0200 (Thu, 22 Sep 2005) $
// $LastChangedRevision: 774 $
// $LastChangedBy: orbiter $
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// Using this software in any meaning (reading, learning, copying, compiling,
// running) means that you agree that the Author(s) is (are) not responsible
// for cost, loss of data or any harm that may be caused directly or indirectly
// by usage of this softare or this documentation. The usage of this software
// is on your own risk. The installation and usage (starting/running) of this
// software may allow other people or application to access your computer and
// any attached devices and is highly dependent on the configuration of the
// software which must be done by the user of the software; the author(s) is
// (are) also not responsible for proper configuration and usage of the
// software, even if provoked by documentation provided together with
// the software.
//
// Any changes to this file according to the GPL as documented in the file
// gpl.txt aside this file in the shipment you received can be done to the
// lines that follows this copyright notice here, but changes must not be
// done inside the copyright notive above. A re-distribution must contain
// the intact and unchanged copyright notice.
// Contributions and changes to the program code must be marked as such.
package de.anomic.kelondro;
public interface kelondroCoding {
public char encodeByte(byte b);
public byte decodeByte(char b);
public String encodeLongSmart(long c, int length);
public String encodeLong(long c, int length);
public long decodeLong(String s);
public String encodeString(String in);
public String decodeString(String in);
public String encode(byte[] in);
public byte[] decode(String in);
}

@ -52,154 +52,6 @@ import java.util.StringTokenizer;
public final class serverCodings {
// this provides encoding and decoding of long cardinals into a 6-bit - based number format
// expressed by a string. This is probably the most compact form to encode numbers as strings.
// the resulting string is filename-friendly, it contains no special character that is not
// suitable for file names.
public static final serverCodings standardCoder = new serverCodings(true);
public static final serverCodings enhancedCoder = new serverCodings(false);
final boolean rfc1113compliant;
public final char[] alpha;
public final byte[] ahpla;
public serverCodings(boolean rfc1113compliant) {
// if we choose not to be rfc1113compliant,
// then we get shorter base64 results which are also filename-compatible
this.rfc1113compliant = rfc1113compliant;
alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray();
if (!(rfc1113compliant)) {
alpha[62] = '-';
alpha[63] = '_';
}
ahpla = new byte[256];
for (int i = 0; i < 256; i++) ahpla[i] = -1;
for (int i = 0; i < alpha.length; i++) ahpla[alpha[i]] = (byte) i;
}
/*
public char encodeBase64Byte(byte b) {
return (char) alpha[b];
}
public byte decodeBase64Byte(char b) {
return ahpla[b];
}
public String encodeBase64LongSmart(long c, int length) {
if (c >= maxBase64(length)) {
StringBuffer s = new StringBuffer(length);
s.setLength(length);
while (length > 0) {
s.setCharAt(--length, alpha[0]);
}
return s.toString();
} else {
return encodeBase64Long(c, length);
}
}
public String encodeBase64Long(long c, int length) {
StringBuffer s = new StringBuffer(length);
s.setLength(length);
while (length > 0) {
s.setCharAt(--length, alpha[(byte) (c & 0x3F)]);
c >>= 6;
}
return s.toString();
}
public long decodeBase64Long(String s) {
while (s.endsWith("=")) s = s.substring(0, s.length() - 1);
long c = 0;
for (int i = 0; i < s.length(); i++) {
c <<= 6;
c += ahpla[s.charAt(i)];
}
return c;
}
public static long maxBase64(int len) {
// computes the maximum number that can be coded with a base64-encoded String of base len
long c = 0;
for (int i = 0; i < len; i++) {
c <<= 6;
c += 63;
}
return c;
}
public String encodeBase64String(String in) {
return encodeBase64(in.getBytes());
}
// we will use this encoding to encode strings with 2^8 values to b64-Strings
// we will do that by grouping each three input bytes to four output bytes.
public String encodeBase64(byte[] in) {
StringBuffer out = new StringBuffer(in.length / 3 * 4 + 3);
int pos = 0;
long l;
while (in.length - pos >= 3) {
l = ((((0XffL & (long) in[pos]) << 8) + (0XffL & (long) in[pos + 1])) << 8) + (0XffL & (long) in[pos + 2]);
pos += 3;
out = out.append(encodeBase64Long(l, 4));
}
// now there may be remaining bytes
if (in.length % 3 != 0)
out = out.append(
(in.length % 3 == 2) ?
encodeBase64Long((((0XffL & (long) in[pos]) << 8) + (0XffL & (long) in[pos + 1])) << 8, 4).substring(0,3) :
encodeBase64Long((((0XffL & (long) in[pos])) << 8) << 8, 4).substring(0, 2));
if (rfc1113compliant) while (out.length() % 4 > 0) out.append("=");
// return result
return out.toString();
}
public String decodeBase64String(String in) {
try {
return new String(decodeBase64(in), "ISO-8859-1");
} catch (java.io.UnsupportedEncodingException e) {
System.out.println("internal error in base64: " + e.getMessage());
return null;
}
}
public byte[] decodeBase64(String in) {
try {
int posIn = 0;
int posOut = 0;
if (rfc1113compliant) while (in.charAt(in.length() - 1) == '=') in = in.substring(0, in.length() - 1);
byte[] out = new byte[in.length() / 4 * 3 + (((in.length() % 4) == 0) ? 0 : in.length() % 4 - 1)];
long l;
while (posIn + 3 < in.length()) {
l = decodeBase64Long(in.substring(posIn, posIn + 4));
out[posOut+2] = (byte) (l % 256); l = l / 256;
out[posOut+1] = (byte) (l % 256); l = l / 256;
out[posOut ] = (byte) (l % 256); l = l / 256;
posIn += 4;
posOut += 3;
}
if (posIn < in.length()) {
if (in.length() - posIn == 3) {
l = decodeBase64Long(in.substring(posIn) + "A");
l = l / 256;
out[posOut+1] = (byte) (l % 256); l = l / 256;
out[posOut ] = (byte) (l % 256); l = l / 256;
} else {
l = decodeBase64Long(in.substring(posIn) + "AA");
l = l / 256 / 256;
out[posOut ] = (byte) (l % 256); l = l / 256;
}
}
return out;
} catch (ArrayIndexOutOfBoundsException e) {
// maybe the input was not base64
throw new RuntimeException("input probably not base64");
}
}
*/
public static String encodeHex(long in, int length) {
String s = Long.toHexString(in);
while (s.length() < length) s = "0" + s;
@ -222,25 +74,6 @@ public final class serverCodings {
return result;
}
/*
public static String encodeMD5B64(String key, boolean enhanced) {
if (enhanced)
return enhancedCoder.encodeBase64(encodeMD5Raw(key));
else
return standardCoder.encodeBase64(encodeMD5Raw(key));
}
public static String encodeMD5B64(File file, boolean enhanced) {
if (enhanced)
return enhancedCoder.encodeBase64(encodeMD5Raw(file));
else
return standardCoder.encodeBase64(encodeMD5Raw(file));
}
*/
// replace with "kelondroBase64Order.enhancedCoder.encode(serverCodings.encodeMD5Raw("
public static String encodeMD5Hex(String key) {
// generate a hex representation from the md5 of a string
return encodeHex(encodeMD5Raw(key));

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