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com.fireflysource.net.http.common.v2.hpack.Huffman Maven / Gradle / Ivy
package com.fireflysource.net.http.common.v2.hpack;
import com.fireflysource.common.string.Utf8StringBuilder;
import java.nio.ByteBuffer;
public class Huffman {
// Appendix C: Huffman Codes
// http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-12#appendix-C
static final int[][] CODES = {
/* ( 0) |11111111|11000 */ {0x1ff8, 13},
/* ( 1) |11111111|11111111|1011000 */ {0x7fffd8, 23},
/* ( 2) |11111111|11111111|11111110|0010 */ {0xfffffe2, 28},
/* ( 3) |11111111|11111111|11111110|0011 */ {0xfffffe3, 28},
/* ( 4) |11111111|11111111|11111110|0100 */ {0xfffffe4, 28},
/* ( 5) |11111111|11111111|11111110|0101 */ {0xfffffe5, 28},
/* ( 6) |11111111|11111111|11111110|0110 */ {0xfffffe6, 28},
/* ( 7) |11111111|11111111|11111110|0111 */ {0xfffffe7, 28},
/* ( 8) |11111111|11111111|11111110|1000 */ {0xfffffe8, 28},
/* ( 9) |11111111|11111111|11101010 */ {0xffffea, 24},
/* ( 10) |11111111|11111111|11111111|111100 */ {0x3ffffffc, 30},
/* ( 11) |11111111|11111111|11111110|1001 */ {0xfffffe9, 28},
/* ( 12) |11111111|11111111|11111110|1010 */ {0xfffffea, 28},
/* ( 13) |11111111|11111111|11111111|111101 */ {0x3ffffffd, 30},
/* ( 14) |11111111|11111111|11111110|1011 */ {0xfffffeb, 28},
/* ( 15) |11111111|11111111|11111110|1100 */ {0xfffffec, 28},
/* ( 16) |11111111|11111111|11111110|1101 */ {0xfffffed, 28},
/* ( 17) |11111111|11111111|11111110|1110 */ {0xfffffee, 28},
/* ( 18) |11111111|11111111|11111110|1111 */ {0xfffffef, 28},
/* ( 19) |11111111|11111111|11111111|0000 */ {0xffffff0, 28},
/* ( 20) |11111111|11111111|11111111|0001 */ {0xffffff1, 28},
/* ( 21) |11111111|11111111|11111111|0010 */ {0xffffff2, 28},
/* ( 22) |11111111|11111111|11111111|111110 */ {0x3ffffffe, 30},
/* ( 23) |11111111|11111111|11111111|0011 */ {0xffffff3, 28},
/* ( 24) |11111111|11111111|11111111|0100 */ {0xffffff4, 28},
/* ( 25) |11111111|11111111|11111111|0101 */ {0xffffff5, 28},
/* ( 26) |11111111|11111111|11111111|0110 */ {0xffffff6, 28},
/* ( 27) |11111111|11111111|11111111|0111 */ {0xffffff7, 28},
/* ( 28) |11111111|11111111|11111111|1000 */ {0xffffff8, 28},
/* ( 29) |11111111|11111111|11111111|1001 */ {0xffffff9, 28},
/* ( 30) |11111111|11111111|11111111|1010 */ {0xffffffa, 28},
/* ( 31) |11111111|11111111|11111111|1011 */ {0xffffffb, 28},
/*' ' ( 32) |010100 */ {0x14, 6},
/*'!' ( 33) |11111110|00 */ {0x3f8, 10},
/*'"' ( 34) |11111110|01 */ {0x3f9, 10},
/*'#' ( 35) |11111111|1010 */ {0xffa, 12},
/*'$' ( 36) |11111111|11001 */ {0x1ff9, 13},
/*'%' ( 37) |010101 */ {0x15, 6},
/*'&' ( 38) |11111000 */ {0xf8, 8},
/*''' ( 39) |11111111|010 */ {0x7fa, 11},
/*'(' ( 40) |11111110|10 */ {0x3fa, 10},
/*')' ( 41) |11111110|11 */ {0x3fb, 10},
/*'*' ( 42) |11111001 */ {0xf9, 8},
/*'+' ( 43) |11111111|011 */ {0x7fb, 11},
/*',' ( 44) |11111010 */ {0xfa, 8},
/*'-' ( 45) |010110 */ {0x16, 6},
/*'.' ( 46) |010111 */ {0x17, 6},
/*'/' ( 47) |011000 */ {0x18, 6},
/*'0' ( 48) |00000 */ {0x0, 5},
/*'1' ( 49) |00001 */ {0x1, 5},
/*'2' ( 50) |00010 */ {0x2, 5},
/*'3' ( 51) |011001 */ {0x19, 6},
/*'4' ( 52) |011010 */ {0x1a, 6},
/*'5' ( 53) |011011 */ {0x1b, 6},
/*'6' ( 54) |011100 */ {0x1c, 6},
/*'7' ( 55) |011101 */ {0x1d, 6},
/*'8' ( 56) |011110 */ {0x1e, 6},
/*'9' ( 57) |011111 */ {0x1f, 6},
/*':' ( 58) |1011100 */ {0x5c, 7},
/*';' ( 59) |11111011 */ {0xfb, 8},
/*'<' ( 60) |11111111|1111100 */ {0x7ffc, 15},
/*'=' ( 61) |100000 */ {0x20, 6},
/*'>' ( 62) |11111111|1011 */ {0xffb, 12},
/*'?' ( 63) |11111111|00 */ {0x3fc, 10},
/*'@' ( 64) |11111111|11010 */ {0x1ffa, 13},
/*'A' ( 65) |100001 */ {0x21, 6},
/*'B' ( 66) |1011101 */ {0x5d, 7},
/*'C' ( 67) |1011110 */ {0x5e, 7},
/*'D' ( 68) |1011111 */ {0x5f, 7},
/*'E' ( 69) |1100000 */ {0x60, 7},
/*'F' ( 70) |1100001 */ {0x61, 7},
/*'G' ( 71) |1100010 */ {0x62, 7},
/*'H' ( 72) |1100011 */ {0x63, 7},
/*'I' ( 73) |1100100 */ {0x64, 7},
/*'J' ( 74) |1100101 */ {0x65, 7},
/*'K' ( 75) |1100110 */ {0x66, 7},
/*'L' ( 76) |1100111 */ {0x67, 7},
/*'M' ( 77) |1101000 */ {0x68, 7},
/*'N' ( 78) |1101001 */ {0x69, 7},
/*'O' ( 79) |1101010 */ {0x6a, 7},
/*'P' ( 80) |1101011 */ {0x6b, 7},
/*'Q' ( 81) |1101100 */ {0x6c, 7},
/*'R' ( 82) |1101101 */ {0x6d, 7},
/*'S' ( 83) |1101110 */ {0x6e, 7},
/*'T' ( 84) |1101111 */ {0x6f, 7},
/*'U' ( 85) |1110000 */ {0x70, 7},
/*'V' ( 86) |1110001 */ {0x71, 7},
/*'W' ( 87) |1110010 */ {0x72, 7},
/*'X' ( 88) |11111100 */ {0xfc, 8},
/*'Y' ( 89) |1110011 */ {0x73, 7},
/*'Z' ( 90) |11111101 */ {0xfd, 8},
/*'[' ( 91) |11111111|11011 */ {0x1ffb, 13},
/*'\' ( 92) |11111111|11111110|000 */ {0x7fff0, 19},
/*']' ( 93) |11111111|11100 */ {0x1ffc, 13},
/*'^' ( 94) |11111111|111100 */ {0x3ffc, 14},
/*'_' ( 95) |100010 */ {0x22, 6},
/*'`' ( 96) |11111111|1111101 */ {0x7ffd, 15},
/*'a' ( 97) |00011 */ {0x3, 5},
/*'b' ( 98) |100011 */ {0x23, 6},
/*'c' ( 99) |00100 */ {0x4, 5},
/*'d' (100) |100100 */ {0x24, 6},
/*'e' (101) |00101 */ {0x5, 5},
/*'f' (102) |100101 */ {0x25, 6},
/*'g' (103) |100110 */ {0x26, 6},
/*'h' (104) |100111 */ {0x27, 6},
/*'i' (105) |00110 */ {0x6, 5},
/*'j' (106) |1110100 */ {0x74, 7},
/*'k' (107) |1110101 */ {0x75, 7},
/*'l' (108) |101000 */ {0x28, 6},
/*'m' (109) |101001 */ {0x29, 6},
/*'n' (110) |101010 */ {0x2a, 6},
/*'o' (111) |00111 */ {0x7, 5},
/*'p' (112) |101011 */ {0x2b, 6},
/*'q' (113) |1110110 */ {0x76, 7},
/*'r' (114) |101100 */ {0x2c, 6},
/*'s' (115) |01000 */ {0x8, 5},
/*'t' (116) |01001 */ {0x9, 5},
/*'u' (117) |101101 */ {0x2d, 6},
/*'v' (118) |1110111 */ {0x77, 7},
/*'w' (119) |1111000 */ {0x78, 7},
/*'x' (120) |1111001 */ {0x79, 7},
/*'y' (121) |1111010 */ {0x7a, 7},
/*'z' (122) |1111011 */ {0x7b, 7},
/*'{' (123) |11111111|1111110 */ {0x7ffe, 15},
/*'|' (124) |11111111|100 */ {0x7fc, 11},
/*'}' (125) |11111111|111101 */ {0x3ffd, 14},
/*'~' (126) |11111111|11101 */ {0x1ffd, 13},
/* (127) |11111111|11111111|11111111|1100 */ {0xffffffc, 28},
/* (128) |11111111|11111110|0110 */ {0xfffe6, 20},
/* (129) |11111111|11111111|010010 */ {0x3fffd2, 22},
/* (130) |11111111|11111110|0111 */ {0xfffe7, 20},
/* (131) |11111111|11111110|1000 */ {0xfffe8, 20},
/* (132) |11111111|11111111|010011 */ {0x3fffd3, 22},
/* (133) |11111111|11111111|010100 */ {0x3fffd4, 22},
/* (134) |11111111|11111111|010101 */ {0x3fffd5, 22},
/* (135) |11111111|11111111|1011001 */ {0x7fffd9, 23},
/* (136) |11111111|11111111|010110 */ {0x3fffd6, 22},
/* (137) |11111111|11111111|1011010 */ {0x7fffda, 23},
/* (138) |11111111|11111111|1011011 */ {0x7fffdb, 23},
/* (139) |11111111|11111111|1011100 */ {0x7fffdc, 23},
/* (140) |11111111|11111111|1011101 */ {0x7fffdd, 23},
/* (141) |11111111|11111111|1011110 */ {0x7fffde, 23},
/* (142) |11111111|11111111|11101011 */ {0xffffeb, 24},
/* (143) |11111111|11111111|1011111 */ {0x7fffdf, 23},
/* (144) |11111111|11111111|11101100 */ {0xffffec, 24},
/* (145) |11111111|11111111|11101101 */ {0xffffed, 24},
/* (146) |11111111|11111111|010111 */ {0x3fffd7, 22},
/* (147) |11111111|11111111|1100000 */ {0x7fffe0, 23},
/* (148) |11111111|11111111|11101110 */ {0xffffee, 24},
/* (149) |11111111|11111111|1100001 */ {0x7fffe1, 23},
/* (150) |11111111|11111111|1100010 */ {0x7fffe2, 23},
/* (151) |11111111|11111111|1100011 */ {0x7fffe3, 23},
/* (152) |11111111|11111111|1100100 */ {0x7fffe4, 23},
/* (153) |11111111|11111110|11100 */ {0x1fffdc, 21},
/* (154) |11111111|11111111|011000 */ {0x3fffd8, 22},
/* (155) |11111111|11111111|1100101 */ {0x7fffe5, 23},
/* (156) |11111111|11111111|011001 */ {0x3fffd9, 22},
/* (157) |11111111|11111111|1100110 */ {0x7fffe6, 23},
/* (158) |11111111|11111111|1100111 */ {0x7fffe7, 23},
/* (159) |11111111|11111111|11101111 */ {0xffffef, 24},
/* (160) |11111111|11111111|011010 */ {0x3fffda, 22},
/* (161) |11111111|11111110|11101 */ {0x1fffdd, 21},
/* (162) |11111111|11111110|1001 */ {0xfffe9, 20},
/* (163) |11111111|11111111|011011 */ {0x3fffdb, 22},
/* (164) |11111111|11111111|011100 */ {0x3fffdc, 22},
/* (165) |11111111|11111111|1101000 */ {0x7fffe8, 23},
/* (166) |11111111|11111111|1101001 */ {0x7fffe9, 23},
/* (167) |11111111|11111110|11110 */ {0x1fffde, 21},
/* (168) |11111111|11111111|1101010 */ {0x7fffea, 23},
/* (169) |11111111|11111111|011101 */ {0x3fffdd, 22},
/* (170) |11111111|11111111|011110 */ {0x3fffde, 22},
/* (171) |11111111|11111111|11110000 */ {0xfffff0, 24},
/* (172) |11111111|11111110|11111 */ {0x1fffdf, 21},
/* (173) |11111111|11111111|011111 */ {0x3fffdf, 22},
/* (174) |11111111|11111111|1101011 */ {0x7fffeb, 23},
/* (175) |11111111|11111111|1101100 */ {0x7fffec, 23},
/* (176) |11111111|11111111|00000 */ {0x1fffe0, 21},
/* (177) |11111111|11111111|00001 */ {0x1fffe1, 21},
/* (178) |11111111|11111111|100000 */ {0x3fffe0, 22},
/* (179) |11111111|11111111|00010 */ {0x1fffe2, 21},
/* (180) |11111111|11111111|1101101 */ {0x7fffed, 23},
/* (181) |11111111|11111111|100001 */ {0x3fffe1, 22},
/* (182) |11111111|11111111|1101110 */ {0x7fffee, 23},
/* (183) |11111111|11111111|1101111 */ {0x7fffef, 23},
/* (184) |11111111|11111110|1010 */ {0xfffea, 20},
/* (185) |11111111|11111111|100010 */ {0x3fffe2, 22},
/* (186) |11111111|11111111|100011 */ {0x3fffe3, 22},
/* (187) |11111111|11111111|100100 */ {0x3fffe4, 22},
/* (188) |11111111|11111111|1110000 */ {0x7ffff0, 23},
/* (189) |11111111|11111111|100101 */ {0x3fffe5, 22},
/* (190) |11111111|11111111|100110 */ {0x3fffe6, 22},
/* (191) |11111111|11111111|1110001 */ {0x7ffff1, 23},
/* (192) |11111111|11111111|11111000|00 */ {0x3ffffe0, 26},
/* (193) |11111111|11111111|11111000|01 */ {0x3ffffe1, 26},
/* (194) |11111111|11111110|1011 */ {0xfffeb, 20},
/* (195) |11111111|11111110|001 */ {0x7fff1, 19},
/* (196) |11111111|11111111|100111 */ {0x3fffe7, 22},
/* (197) |11111111|11111111|1110010 */ {0x7ffff2, 23},
/* (198) |11111111|11111111|101000 */ {0x3fffe8, 22},
/* (199) |11111111|11111111|11110110|0 */ {0x1ffffec, 25},
/* (200) |11111111|11111111|11111000|10 */ {0x3ffffe2, 26},
/* (201) |11111111|11111111|11111000|11 */ {0x3ffffe3, 26},
/* (202) |11111111|11111111|11111001|00 */ {0x3ffffe4, 26},
/* (203) |11111111|11111111|11111011|110 */ {0x7ffffde, 27},
/* (204) |11111111|11111111|11111011|111 */ {0x7ffffdf, 27},
/* (205) |11111111|11111111|11111001|01 */ {0x3ffffe5, 26},
/* (206) |11111111|11111111|11110001 */ {0xfffff1, 24},
/* (207) |11111111|11111111|11110110|1 */ {0x1ffffed, 25},
/* (208) |11111111|11111110|010 */ {0x7fff2, 19},
/* (209) |11111111|11111111|00011 */ {0x1fffe3, 21},
/* (210) |11111111|11111111|11111001|10 */ {0x3ffffe6, 26},
/* (211) |11111111|11111111|11111100|000 */ {0x7ffffe0, 27},
/* (212) |11111111|11111111|11111100|001 */ {0x7ffffe1, 27},
/* (213) |11111111|11111111|11111001|11 */ {0x3ffffe7, 26},
/* (214) |11111111|11111111|11111100|010 */ {0x7ffffe2, 27},
/* (215) |11111111|11111111|11110010 */ {0xfffff2, 24},
/* (216) |11111111|11111111|00100 */ {0x1fffe4, 21},
/* (217) |11111111|11111111|00101 */ {0x1fffe5, 21},
/* (218) |11111111|11111111|11111010|00 */ {0x3ffffe8, 26},
/* (219) |11111111|11111111|11111010|01 */ {0x3ffffe9, 26},
/* (220) |11111111|11111111|11111111|1101 */ {0xffffffd, 28},
/* (221) |11111111|11111111|11111100|011 */ {0x7ffffe3, 27},
/* (222) |11111111|11111111|11111100|100 */ {0x7ffffe4, 27},
/* (223) |11111111|11111111|11111100|101 */ {0x7ffffe5, 27},
/* (224) |11111111|11111110|1100 */ {0xfffec, 20},
/* (225) |11111111|11111111|11110011 */ {0xfffff3, 24},
/* (226) |11111111|11111110|1101 */ {0xfffed, 20},
/* (227) |11111111|11111111|00110 */ {0x1fffe6, 21},
/* (228) |11111111|11111111|101001 */ {0x3fffe9, 22},
/* (229) |11111111|11111111|00111 */ {0x1fffe7, 21},
/* (230) |11111111|11111111|01000 */ {0x1fffe8, 21},
/* (231) |11111111|11111111|1110011 */ {0x7ffff3, 23},
/* (232) |11111111|11111111|101010 */ {0x3fffea, 22},
/* (233) |11111111|11111111|101011 */ {0x3fffeb, 22},
/* (234) |11111111|11111111|11110111|0 */ {0x1ffffee, 25},
/* (235) |11111111|11111111|11110111|1 */ {0x1ffffef, 25},
/* (236) |11111111|11111111|11110100 */ {0xfffff4, 24},
/* (237) |11111111|11111111|11110101 */ {0xfffff5, 24},
/* (238) |11111111|11111111|11111010|10 */ {0x3ffffea, 26},
/* (239) |11111111|11111111|1110100 */ {0x7ffff4, 23},
/* (240) |11111111|11111111|11111010|11 */ {0x3ffffeb, 26},
/* (241) |11111111|11111111|11111100|110 */ {0x7ffffe6, 27},
/* (242) |11111111|11111111|11111011|00 */ {0x3ffffec, 26},
/* (243) |11111111|11111111|11111011|01 */ {0x3ffffed, 26},
/* (244) |11111111|11111111|11111100|111 */ {0x7ffffe7, 27},
/* (245) |11111111|11111111|11111101|000 */ {0x7ffffe8, 27},
/* (246) |11111111|11111111|11111101|001 */ {0x7ffffe9, 27},
/* (247) |11111111|11111111|11111101|010 */ {0x7ffffea, 27},
/* (248) |11111111|11111111|11111101|011 */ {0x7ffffeb, 27},
/* (249) |11111111|11111111|11111111|1110 */ {0xffffffe, 28},
/* (250) |11111111|11111111|11111101|100 */ {0x7ffffec, 27},
/* (251) |11111111|11111111|11111101|101 */ {0x7ffffed, 27},
/* (252) |11111111|11111111|11111101|110 */ {0x7ffffee, 27},
/* (253) |11111111|11111111|11111101|111 */ {0x7ffffef, 27},
/* (254) |11111111|11111111|11111110|000 */ {0x7fffff0, 27},
/* (255) |11111111|11111111|11111011|10 */ {0x3ffffee, 26},
/*EOS (256) |11111111|11111111|11111111|111111 */ {0x3fffffff, 30}
};
static final int[][] LCCODES = new int[CODES.length][];
static final char EOS = 256;
// Huffman decode tree stored in a flattened char array for good
// locality of reference.
static final char[] tree;
static final char[] rowsym;
static final byte[] rowbits;
// Build the Huffman lookup tree and LC TABLE
static {
System.arraycopy(CODES, 0, LCCODES, 0, CODES.length);
for (int i = 'A'; i <= 'Z'; i++) {
LCCODES[i] = LCCODES['a' + i - 'A'];
}
int r = 0;
for (int i = 0; i < CODES.length; i++) {
r += (CODES[i][1] + 7) / 8;
}
tree = new char[r * 256];
rowsym = new char[r];
rowbits = new byte[r];
r = 0;
for (int sym = 0; sym < CODES.length; sym++) {
int code = CODES[sym][0];
int len = CODES[sym][1];
int current = 0;
while (len > 8) {
len -= 8;
int i = ((code >>> len) & 0xFF);
int t = current * 256 + i;
current = tree[t];
if (current == 0) {
tree[t] = (char) ++r;
current = r;
}
}
int terminal = ++r;
rowsym[r] = (char) sym;
int b = len & 0x07;
int terminalBits = b == 0 ? 8 : b;
rowbits[r] = (byte) terminalBits;
int shift = 8 - len;
int start = current * 256 + ((code << shift) & 0xFF);
int end = start + (1 << shift);
for (int i = start; i < end; i++) {
tree[i] = (char) terminal;
}
}
}
public static String decode(ByteBuffer buffer) throws HpackException.CompressionException {
return decode(buffer, buffer.remaining());
}
public static String decode(ByteBuffer buffer, int length) throws HpackException.CompressionException {
Utf8StringBuilder utf8 = new Utf8StringBuilder(length * 2);
int node = 0;
int current = 0;
int bits = 0;
for (int i = 0; i < length; i++) {
int b = buffer.get() & 0xFF;
current = (current << 8) | b;
bits += 8;
while (bits >= 8) {
int c = (current >>> (bits - 8)) & 0xFF;
node = tree[node * 256 + c];
if (rowbits[node] != 0) {
if (rowsym[node] == EOS)
throw new HpackException.CompressionException("EOS in content");
// terminal node
utf8.append((byte) (0xFF & rowsym[node]));
bits -= rowbits[node];
node = 0;
} else {
// non-terminal node
bits -= 8;
}
}
}
while (bits > 0) {
int c = (current << (8 - bits)) & 0xFF;
int lastNode = node;
node = tree[node * 256 + c];
if (rowbits[node] == 0 || rowbits[node] > bits) {
int requiredPadding = 0;
for (int i = 0; i < bits; i++) {
requiredPadding = (requiredPadding << 1) | 1;
}
if ((c >> (8 - bits)) != requiredPadding)
throw new HpackException.CompressionException("Incorrect padding");
node = lastNode;
break;
}
utf8.append((byte) (0xFF & rowsym[node]));
bits -= rowbits[node];
node = 0;
}
if (node != 0)
throw new HpackException.CompressionException("Bad termination");
return utf8.toString();
}
public static int octetsNeeded(String s) {
return octetsNeeded(CODES, s);
}
public static int octetsNeeded(byte[] b) {
return octetsNeeded(CODES, b);
}
public static void encode(ByteBuffer buffer, String s) {
encode(CODES, buffer, s);
}
public static void encode(ByteBuffer buffer, byte[] b) {
encode(CODES, buffer, b);
}
public static int octetsNeededLC(String s) {
return octetsNeeded(LCCODES, s);
}
public static void encodeLC(ByteBuffer buffer, String s) {
encode(LCCODES, buffer, s);
}
private static int octetsNeeded(final int[][] table, String s) {
int needed = 0;
int len = s.length();
for (int i = 0; i < len; i++) {
char c = s.charAt(i);
if (c >= 128 || c < ' ')
return -1;
needed += table[c][1];
}
return (needed + 7) / 8;
}
private static int octetsNeeded(final int[][] table, byte[] b) {
int needed = 0;
int len = b.length;
for (int i = 0; i < len; i++) {
int c = 0xFF & b[i];
needed += table[c][1];
}
return (needed + 7) / 8;
}
/**
* @param table The table to encode by
* @param buffer The buffer to encode to
* @param s The string to encode
*/
private static void encode(final int[][] table, ByteBuffer buffer, String s) {
long current = 0;
int n = 0;
int len = s.length();
for (int i = 0; i < len; i++) {
char c = s.charAt(i);
if (c >= 128 || c < ' ')
throw new IllegalArgumentException();
int code = table[c][0];
int bits = table[c][1];
current <<= bits;
current |= code;
n += bits;
while (n >= 8) {
n -= 8;
buffer.put((byte) (current >> n));
}
}
if (n > 0) {
current <<= (8 - n);
current |= (0xFF >>> n);
buffer.put((byte) (current));
}
}
private static void encode(final int[][] table, ByteBuffer buffer, byte[] b) {
long current = 0;
int n = 0;
int len = b.length;
for (int i = 0; i < len; i++) {
int c = 0xFF & b[i];
int code = table[c][0];
int bits = table[c][1];
current <<= bits;
current |= code;
n += bits;
while (n >= 8) {
n -= 8;
buffer.put((byte) (current >> n));
}
}
if (n > 0) {
current <<= (8 - n);
current |= (0xFF >>> n);
buffer.put((byte) (current));
}
}
}