in java/org/apache/coyote/http2/HPackHuffman.java [45:363]
static {
HuffmanCode[] codes = new HuffmanCode[257];
codes[0] = new HuffmanCode(0x1ff8, 13);
codes[1] = new HuffmanCode(0x7fffd8, 23);
codes[2] = new HuffmanCode(0xfffffe2, 28);
codes[3] = new HuffmanCode(0xfffffe3, 28);
codes[4] = new HuffmanCode(0xfffffe4, 28);
codes[5] = new HuffmanCode(0xfffffe5, 28);
codes[6] = new HuffmanCode(0xfffffe6, 28);
codes[7] = new HuffmanCode(0xfffffe7, 28);
codes[8] = new HuffmanCode(0xfffffe8, 28);
codes[9] = new HuffmanCode(0xffffea, 24);
codes[10] = new HuffmanCode(0x3ffffffc, 30);
codes[11] = new HuffmanCode(0xfffffe9, 28);
codes[12] = new HuffmanCode(0xfffffea, 28);
codes[13] = new HuffmanCode(0x3ffffffd, 30);
codes[14] = new HuffmanCode(0xfffffeb, 28);
codes[15] = new HuffmanCode(0xfffffec, 28);
codes[16] = new HuffmanCode(0xfffffed, 28);
codes[17] = new HuffmanCode(0xfffffee, 28);
codes[18] = new HuffmanCode(0xfffffef, 28);
codes[19] = new HuffmanCode(0xffffff0, 28);
codes[20] = new HuffmanCode(0xffffff1, 28);
codes[21] = new HuffmanCode(0xffffff2, 28);
codes[22] = new HuffmanCode(0x3ffffffe, 30);
codes[23] = new HuffmanCode(0xffffff3, 28);
codes[24] = new HuffmanCode(0xffffff4, 28);
codes[25] = new HuffmanCode(0xffffff5, 28);
codes[26] = new HuffmanCode(0xffffff6, 28);
codes[27] = new HuffmanCode(0xffffff7, 28);
codes[28] = new HuffmanCode(0xffffff8, 28);
codes[29] = new HuffmanCode(0xffffff9, 28);
codes[30] = new HuffmanCode(0xffffffa, 28);
codes[31] = new HuffmanCode(0xffffffb, 28);
codes[32] = new HuffmanCode(0x14, 6);
codes[33] = new HuffmanCode(0x3f8, 10);
codes[34] = new HuffmanCode(0x3f9, 10);
codes[35] = new HuffmanCode(0xffa, 12);
codes[36] = new HuffmanCode(0x1ff9, 13);
codes[37] = new HuffmanCode(0x15, 6);
codes[38] = new HuffmanCode(0xf8, 8);
codes[39] = new HuffmanCode(0x7fa, 11);
codes[40] = new HuffmanCode(0x3fa, 10);
codes[41] = new HuffmanCode(0x3fb, 10);
codes[42] = new HuffmanCode(0xf9, 8);
codes[43] = new HuffmanCode(0x7fb, 11);
codes[44] = new HuffmanCode(0xfa, 8);
codes[45] = new HuffmanCode(0x16, 6);
codes[46] = new HuffmanCode(0x17, 6);
codes[47] = new HuffmanCode(0x18, 6);
codes[48] = new HuffmanCode(0x0, 5);
codes[49] = new HuffmanCode(0x1, 5);
codes[50] = new HuffmanCode(0x2, 5);
codes[51] = new HuffmanCode(0x19, 6);
codes[52] = new HuffmanCode(0x1a, 6);
codes[53] = new HuffmanCode(0x1b, 6);
codes[54] = new HuffmanCode(0x1c, 6);
codes[55] = new HuffmanCode(0x1d, 6);
codes[56] = new HuffmanCode(0x1e, 6);
codes[57] = new HuffmanCode(0x1f, 6);
codes[58] = new HuffmanCode(0x5c, 7);
codes[59] = new HuffmanCode(0xfb, 8);
codes[60] = new HuffmanCode(0x7ffc, 15);
codes[61] = new HuffmanCode(0x20, 6);
codes[62] = new HuffmanCode(0xffb, 12);
codes[63] = new HuffmanCode(0x3fc, 10);
codes[64] = new HuffmanCode(0x1ffa, 13);
codes[65] = new HuffmanCode(0x21, 6);
codes[66] = new HuffmanCode(0x5d, 7);
codes[67] = new HuffmanCode(0x5e, 7);
codes[68] = new HuffmanCode(0x5f, 7);
codes[69] = new HuffmanCode(0x60, 7);
codes[70] = new HuffmanCode(0x61, 7);
codes[71] = new HuffmanCode(0x62, 7);
codes[72] = new HuffmanCode(0x63, 7);
codes[73] = new HuffmanCode(0x64, 7);
codes[74] = new HuffmanCode(0x65, 7);
codes[75] = new HuffmanCode(0x66, 7);
codes[76] = new HuffmanCode(0x67, 7);
codes[77] = new HuffmanCode(0x68, 7);
codes[78] = new HuffmanCode(0x69, 7);
codes[79] = new HuffmanCode(0x6a, 7);
codes[80] = new HuffmanCode(0x6b, 7);
codes[81] = new HuffmanCode(0x6c, 7);
codes[82] = new HuffmanCode(0x6d, 7);
codes[83] = new HuffmanCode(0x6e, 7);
codes[84] = new HuffmanCode(0x6f, 7);
codes[85] = new HuffmanCode(0x70, 7);
codes[86] = new HuffmanCode(0x71, 7);
codes[87] = new HuffmanCode(0x72, 7);
codes[88] = new HuffmanCode(0xfc, 8);
codes[89] = new HuffmanCode(0x73, 7);
codes[90] = new HuffmanCode(0xfd, 8);
codes[91] = new HuffmanCode(0x1ffb, 13);
codes[92] = new HuffmanCode(0x7fff0, 19);
codes[93] = new HuffmanCode(0x1ffc, 13);
codes[94] = new HuffmanCode(0x3ffc, 14);
codes[95] = new HuffmanCode(0x22, 6);
codes[96] = new HuffmanCode(0x7ffd, 15);
codes[97] = new HuffmanCode(0x3, 5);
codes[98] = new HuffmanCode(0x23, 6);
codes[99] = new HuffmanCode(0x4, 5);
codes[100] = new HuffmanCode(0x24, 6);
codes[101] = new HuffmanCode(0x5, 5);
codes[102] = new HuffmanCode(0x25, 6);
codes[103] = new HuffmanCode(0x26, 6);
codes[104] = new HuffmanCode(0x27, 6);
codes[105] = new HuffmanCode(0x6, 5);
codes[106] = new HuffmanCode(0x74, 7);
codes[107] = new HuffmanCode(0x75, 7);
codes[108] = new HuffmanCode(0x28, 6);
codes[109] = new HuffmanCode(0x29, 6);
codes[110] = new HuffmanCode(0x2a, 6);
codes[111] = new HuffmanCode(0x7, 5);
codes[112] = new HuffmanCode(0x2b, 6);
codes[113] = new HuffmanCode(0x76, 7);
codes[114] = new HuffmanCode(0x2c, 6);
codes[115] = new HuffmanCode(0x8, 5);
codes[116] = new HuffmanCode(0x9, 5);
codes[117] = new HuffmanCode(0x2d, 6);
codes[118] = new HuffmanCode(0x77, 7);
codes[119] = new HuffmanCode(0x78, 7);
codes[120] = new HuffmanCode(0x79, 7);
codes[121] = new HuffmanCode(0x7a, 7);
codes[122] = new HuffmanCode(0x7b, 7);
codes[123] = new HuffmanCode(0x7ffe, 15);
codes[124] = new HuffmanCode(0x7fc, 11);
codes[125] = new HuffmanCode(0x3ffd, 14);
codes[126] = new HuffmanCode(0x1ffd, 13);
codes[127] = new HuffmanCode(0xffffffc, 28);
codes[128] = new HuffmanCode(0xfffe6, 20);
codes[129] = new HuffmanCode(0x3fffd2, 22);
codes[130] = new HuffmanCode(0xfffe7, 20);
codes[131] = new HuffmanCode(0xfffe8, 20);
codes[132] = new HuffmanCode(0x3fffd3, 22);
codes[133] = new HuffmanCode(0x3fffd4, 22);
codes[134] = new HuffmanCode(0x3fffd5, 22);
codes[135] = new HuffmanCode(0x7fffd9, 23);
codes[136] = new HuffmanCode(0x3fffd6, 22);
codes[137] = new HuffmanCode(0x7fffda, 23);
codes[138] = new HuffmanCode(0x7fffdb, 23);
codes[139] = new HuffmanCode(0x7fffdc, 23);
codes[140] = new HuffmanCode(0x7fffdd, 23);
codes[141] = new HuffmanCode(0x7fffde, 23);
codes[142] = new HuffmanCode(0xffffeb, 24);
codes[143] = new HuffmanCode(0x7fffdf, 23);
codes[144] = new HuffmanCode(0xffffec, 24);
codes[145] = new HuffmanCode(0xffffed, 24);
codes[146] = new HuffmanCode(0x3fffd7, 22);
codes[147] = new HuffmanCode(0x7fffe0, 23);
codes[148] = new HuffmanCode(0xffffee, 24);
codes[149] = new HuffmanCode(0x7fffe1, 23);
codes[150] = new HuffmanCode(0x7fffe2, 23);
codes[151] = new HuffmanCode(0x7fffe3, 23);
codes[152] = new HuffmanCode(0x7fffe4, 23);
codes[153] = new HuffmanCode(0x1fffdc, 21);
codes[154] = new HuffmanCode(0x3fffd8, 22);
codes[155] = new HuffmanCode(0x7fffe5, 23);
codes[156] = new HuffmanCode(0x3fffd9, 22);
codes[157] = new HuffmanCode(0x7fffe6, 23);
codes[158] = new HuffmanCode(0x7fffe7, 23);
codes[159] = new HuffmanCode(0xffffef, 24);
codes[160] = new HuffmanCode(0x3fffda, 22);
codes[161] = new HuffmanCode(0x1fffdd, 21);
codes[162] = new HuffmanCode(0xfffe9, 20);
codes[163] = new HuffmanCode(0x3fffdb, 22);
codes[164] = new HuffmanCode(0x3fffdc, 22);
codes[165] = new HuffmanCode(0x7fffe8, 23);
codes[166] = new HuffmanCode(0x7fffe9, 23);
codes[167] = new HuffmanCode(0x1fffde, 21);
codes[168] = new HuffmanCode(0x7fffea, 23);
codes[169] = new HuffmanCode(0x3fffdd, 22);
codes[170] = new HuffmanCode(0x3fffde, 22);
codes[171] = new HuffmanCode(0xfffff0, 24);
codes[172] = new HuffmanCode(0x1fffdf, 21);
codes[173] = new HuffmanCode(0x3fffdf, 22);
codes[174] = new HuffmanCode(0x7fffeb, 23);
codes[175] = new HuffmanCode(0x7fffec, 23);
codes[176] = new HuffmanCode(0x1fffe0, 21);
codes[177] = new HuffmanCode(0x1fffe1, 21);
codes[178] = new HuffmanCode(0x3fffe0, 22);
codes[179] = new HuffmanCode(0x1fffe2, 21);
codes[180] = new HuffmanCode(0x7fffed, 23);
codes[181] = new HuffmanCode(0x3fffe1, 22);
codes[182] = new HuffmanCode(0x7fffee, 23);
codes[183] = new HuffmanCode(0x7fffef, 23);
codes[184] = new HuffmanCode(0xfffea, 20);
codes[185] = new HuffmanCode(0x3fffe2, 22);
codes[186] = new HuffmanCode(0x3fffe3, 22);
codes[187] = new HuffmanCode(0x3fffe4, 22);
codes[188] = new HuffmanCode(0x7ffff0, 23);
codes[189] = new HuffmanCode(0x3fffe5, 22);
codes[190] = new HuffmanCode(0x3fffe6, 22);
codes[191] = new HuffmanCode(0x7ffff1, 23);
codes[192] = new HuffmanCode(0x3ffffe0, 26);
codes[193] = new HuffmanCode(0x3ffffe1, 26);
codes[194] = new HuffmanCode(0xfffeb, 20);
codes[195] = new HuffmanCode(0x7fff1, 19);
codes[196] = new HuffmanCode(0x3fffe7, 22);
codes[197] = new HuffmanCode(0x7ffff2, 23);
codes[198] = new HuffmanCode(0x3fffe8, 22);
codes[199] = new HuffmanCode(0x1ffffec, 25);
codes[200] = new HuffmanCode(0x3ffffe2, 26);
codes[201] = new HuffmanCode(0x3ffffe3, 26);
codes[202] = new HuffmanCode(0x3ffffe4, 26);
codes[203] = new HuffmanCode(0x7ffffde, 27);
codes[204] = new HuffmanCode(0x7ffffdf, 27);
codes[205] = new HuffmanCode(0x3ffffe5, 26);
codes[206] = new HuffmanCode(0xfffff1, 24);
codes[207] = new HuffmanCode(0x1ffffed, 25);
codes[208] = new HuffmanCode(0x7fff2, 19);
codes[209] = new HuffmanCode(0x1fffe3, 21);
codes[210] = new HuffmanCode(0x3ffffe6, 26);
codes[211] = new HuffmanCode(0x7ffffe0, 27);
codes[212] = new HuffmanCode(0x7ffffe1, 27);
codes[213] = new HuffmanCode(0x3ffffe7, 26);
codes[214] = new HuffmanCode(0x7ffffe2, 27);
codes[215] = new HuffmanCode(0xfffff2, 24);
codes[216] = new HuffmanCode(0x1fffe4, 21);
codes[217] = new HuffmanCode(0x1fffe5, 21);
codes[218] = new HuffmanCode(0x3ffffe8, 26);
codes[219] = new HuffmanCode(0x3ffffe9, 26);
codes[220] = new HuffmanCode(0xffffffd, 28);
codes[221] = new HuffmanCode(0x7ffffe3, 27);
codes[222] = new HuffmanCode(0x7ffffe4, 27);
codes[223] = new HuffmanCode(0x7ffffe5, 27);
codes[224] = new HuffmanCode(0xfffec, 20);
codes[225] = new HuffmanCode(0xfffff3, 24);
codes[226] = new HuffmanCode(0xfffed, 20);
codes[227] = new HuffmanCode(0x1fffe6, 21);
codes[228] = new HuffmanCode(0x3fffe9, 22);
codes[229] = new HuffmanCode(0x1fffe7, 21);
codes[230] = new HuffmanCode(0x1fffe8, 21);
codes[231] = new HuffmanCode(0x7ffff3, 23);
codes[232] = new HuffmanCode(0x3fffea, 22);
codes[233] = new HuffmanCode(0x3fffeb, 22);
codes[234] = new HuffmanCode(0x1ffffee, 25);
codes[235] = new HuffmanCode(0x1ffffef, 25);
codes[236] = new HuffmanCode(0xfffff4, 24);
codes[237] = new HuffmanCode(0xfffff5, 24);
codes[238] = new HuffmanCode(0x3ffffea, 26);
codes[239] = new HuffmanCode(0x7ffff4, 23);
codes[240] = new HuffmanCode(0x3ffffeb, 26);
codes[241] = new HuffmanCode(0x7ffffe6, 27);
codes[242] = new HuffmanCode(0x3ffffec, 26);
codes[243] = new HuffmanCode(0x3ffffed, 26);
codes[244] = new HuffmanCode(0x7ffffe7, 27);
codes[245] = new HuffmanCode(0x7ffffe8, 27);
codes[246] = new HuffmanCode(0x7ffffe9, 27);
codes[247] = new HuffmanCode(0x7ffffea, 27);
codes[248] = new HuffmanCode(0x7ffffeb, 27);
codes[249] = new HuffmanCode(0xffffffe, 28);
codes[250] = new HuffmanCode(0x7ffffec, 27);
codes[251] = new HuffmanCode(0x7ffffed, 27);
codes[252] = new HuffmanCode(0x7ffffee, 27);
codes[253] = new HuffmanCode(0x7ffffef, 27);
codes[254] = new HuffmanCode(0x7fffff0, 27);
codes[255] = new HuffmanCode(0x3ffffee, 26);
codes[256] = new HuffmanCode(0x3fffffff, 30);
HUFFMAN_CODES = codes;
// lengths determined by experimentation, just set it to something large then see how large it actually ends up
int[] codingTree = new int[256];
// the current position in the tree
int pos = 0;
int allocated = 1; // the next position to allocate to
// map of the current state at a given position
// only used while building the tree
HuffmanCode[] currentCode = new HuffmanCode[256];
currentCode[0] = new HuffmanCode(0, 0);
final Set<HuffmanCode> allCodes = new HashSet<>(Arrays.asList(HUFFMAN_CODES));
while (!allCodes.isEmpty()) {
int length = currentCode[pos].length;
int code = currentCode[pos].value;
int newLength = length + 1;
HuffmanCode high = new HuffmanCode(code << 1 | 1, newLength);
HuffmanCode low = new HuffmanCode(code << 1, newLength);
int newVal;
boolean highTerminal = allCodes.remove(high);
if (highTerminal) {
// bah, linear search
int i;
for (i = 0; i < codes.length; ++i) {
if (codes[i].equals(high)) {
break;
}
}
newVal = LOW_TERMINAL_BIT | i;
} else {
int highPos = allocated++;
currentCode[highPos] = high;
newVal = highPos;
}
newVal <<= 16;
boolean lowTerminal = allCodes.remove(low);
if (lowTerminal) {
// bah, linear search
int i;
for (i = 0; i < codes.length; ++i) {
if (codes[i].equals(low)) {
break;
}
}
newVal |= LOW_TERMINAL_BIT | i;
} else {
int lowPos = allocated++;
currentCode[lowPos] = low;
newVal |= lowPos;
}
codingTree[pos] = newVal;
pos++;
}
DECODING_TABLE = codingTree;
}