org.glassfish.grizzly.http2.hpack.HuffmanCoding Maven / Gradle / Ivy
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* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
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/*
* Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package org.glassfish.grizzly.http2.hpack;
import java.io.IOException;
import java.io.OutputStream;
import static java.lang.String.format;
import org.glassfish.grizzly.Buffer;
public class HuffmanCoding {
private final Code EOS = new Code(0x3fffffff, 30);
private final Code[] codes = new Code[257];
private final Node root = new Node() {
@Override
public String toString() { return "root"; }
};
private static class LazySingletonHolder {
private static final HuffmanCoding INSTANCE = new HuffmanCoding();
}
public static HuffmanCoding getInstance() {
return LazySingletonHolder.INSTANCE;
}
private HuffmanCoding() {
// @formatter:off
addChar(0, 0x1ff8, 13);
addChar(1, 0x7fffd8, 23);
addChar(2, 0xfffffe2, 28);
addChar(3, 0xfffffe3, 28);
addChar(4, 0xfffffe4, 28);
addChar(5, 0xfffffe5, 28);
addChar(6, 0xfffffe6, 28);
addChar(7, 0xfffffe7, 28);
addChar(8, 0xfffffe8, 28);
addChar(9, 0xffffea, 24);
addChar(10, 0x3ffffffc, 30);
addChar(11, 0xfffffe9, 28);
addChar(12, 0xfffffea, 28);
addChar(13, 0x3ffffffd, 30);
addChar(14, 0xfffffeb, 28);
addChar(15, 0xfffffec, 28);
addChar(16, 0xfffffed, 28);
addChar(17, 0xfffffee, 28);
addChar(18, 0xfffffef, 28);
addChar(19, 0xffffff0, 28);
addChar(20, 0xffffff1, 28);
addChar(21, 0xffffff2, 28);
addChar(22, 0x3ffffffe, 30);
addChar(23, 0xffffff3, 28);
addChar(24, 0xffffff4, 28);
addChar(25, 0xffffff5, 28);
addChar(26, 0xffffff6, 28);
addChar(27, 0xffffff7, 28);
addChar(28, 0xffffff8, 28);
addChar(29, 0xffffff9, 28);
addChar(30, 0xffffffa, 28);
addChar(31, 0xffffffb, 28);
addChar(32, 0x14, 6);
addChar(33, 0x3f8, 10);
addChar(34, 0x3f9, 10);
addChar(35, 0xffa, 12);
addChar(36, 0x1ff9, 13);
addChar(37, 0x15, 6);
addChar(38, 0xf8, 8);
addChar(39, 0x7fa, 11);
addChar(40, 0x3fa, 10);
addChar(41, 0x3fb, 10);
addChar(42, 0xf9, 8);
addChar(43, 0x7fb, 11);
addChar(44, 0xfa, 8);
addChar(45, 0x16, 6);
addChar(46, 0x17, 6);
addChar(47, 0x18, 6);
addChar(48, 0x0, 5);
addChar(49, 0x1, 5);
addChar(50, 0x2, 5);
addChar(51, 0x19, 6);
addChar(52, 0x1a, 6);
addChar(53, 0x1b, 6);
addChar(54, 0x1c, 6);
addChar(55, 0x1d, 6);
addChar(56, 0x1e, 6);
addChar(57, 0x1f, 6);
addChar(58, 0x5c, 7);
addChar(59, 0xfb, 8);
addChar(60, 0x7ffc, 15);
addChar(61, 0x20, 6);
addChar(62, 0xffb, 12);
addChar(63, 0x3fc, 10);
addChar(64, 0x1ffa, 13);
addChar(65, 0x21, 6);
addChar(66, 0x5d, 7);
addChar(67, 0x5e, 7);
addChar(68, 0x5f, 7);
addChar(69, 0x60, 7);
addChar(70, 0x61, 7);
addChar(71, 0x62, 7);
addChar(72, 0x63, 7);
addChar(73, 0x64, 7);
addChar(74, 0x65, 7);
addChar(75, 0x66, 7);
addChar(76, 0x67, 7);
addChar(77, 0x68, 7);
addChar(78, 0x69, 7);
addChar(79, 0x6a, 7);
addChar(80, 0x6b, 7);
addChar(81, 0x6c, 7);
addChar(82, 0x6d, 7);
addChar(83, 0x6e, 7);
addChar(84, 0x6f, 7);
addChar(85, 0x70, 7);
addChar(86, 0x71, 7);
addChar(87, 0x72, 7);
addChar(88, 0xfc, 8);
addChar(89, 0x73, 7);
addChar(90, 0xfd, 8);
addChar(91, 0x1ffb, 13);
addChar(92, 0x7fff0, 19);
addChar(93, 0x1ffc, 13);
addChar(94, 0x3ffc, 14);
addChar(95, 0x22, 6);
addChar(96, 0x7ffd, 15);
addChar(97, 0x3, 5);
addChar(98, 0x23, 6);
addChar(99, 0x4, 5);
addChar(100, 0x24, 6);
addChar(101, 0x5, 5);
addChar(102, 0x25, 6);
addChar(103, 0x26, 6);
addChar(104, 0x27, 6);
addChar(105, 0x6, 5);
addChar(106, 0x74, 7);
addChar(107, 0x75, 7);
addChar(108, 0x28, 6);
addChar(109, 0x29, 6);
addChar(110, 0x2a, 6);
addChar(111, 0x7, 5);
addChar(112, 0x2b, 6);
addChar(113, 0x76, 7);
addChar(114, 0x2c, 6);
addChar(115, 0x8, 5);
addChar(116, 0x9, 5);
addChar(117, 0x2d, 6);
addChar(118, 0x77, 7);
addChar(119, 0x78, 7);
addChar(120, 0x79, 7);
addChar(121, 0x7a, 7);
addChar(122, 0x7b, 7);
addChar(123, 0x7ffe, 15);
addChar(124, 0x7fc, 11);
addChar(125, 0x3ffd, 14);
addChar(126, 0x1ffd, 13);
addChar(127, 0xffffffc, 28);
addChar(128, 0xfffe6, 20);
addChar(129, 0x3fffd2, 22);
addChar(130, 0xfffe7, 20);
addChar(131, 0xfffe8, 20);
addChar(132, 0x3fffd3, 22);
addChar(133, 0x3fffd4, 22);
addChar(134, 0x3fffd5, 22);
addChar(135, 0x7fffd9, 23);
addChar(136, 0x3fffd6, 22);
addChar(137, 0x7fffda, 23);
addChar(138, 0x7fffdb, 23);
addChar(139, 0x7fffdc, 23);
addChar(140, 0x7fffdd, 23);
addChar(141, 0x7fffde, 23);
addChar(142, 0xffffeb, 24);
addChar(143, 0x7fffdf, 23);
addChar(144, 0xffffec, 24);
addChar(145, 0xffffed, 24);
addChar(146, 0x3fffd7, 22);
addChar(147, 0x7fffe0, 23);
addChar(148, 0xffffee, 24);
addChar(149, 0x7fffe1, 23);
addChar(150, 0x7fffe2, 23);
addChar(151, 0x7fffe3, 23);
addChar(152, 0x7fffe4, 23);
addChar(153, 0x1fffdc, 21);
addChar(154, 0x3fffd8, 22);
addChar(155, 0x7fffe5, 23);
addChar(156, 0x3fffd9, 22);
addChar(157, 0x7fffe6, 23);
addChar(158, 0x7fffe7, 23);
addChar(159, 0xffffef, 24);
addChar(160, 0x3fffda, 22);
addChar(161, 0x1fffdd, 21);
addChar(162, 0xfffe9, 20);
addChar(163, 0x3fffdb, 22);
addChar(164, 0x3fffdc, 22);
addChar(165, 0x7fffe8, 23);
addChar(166, 0x7fffe9, 23);
addChar(167, 0x1fffde, 21);
addChar(168, 0x7fffea, 23);
addChar(169, 0x3fffdd, 22);
addChar(170, 0x3fffde, 22);
addChar(171, 0xfffff0, 24);
addChar(172, 0x1fffdf, 21);
addChar(173, 0x3fffdf, 22);
addChar(174, 0x7fffeb, 23);
addChar(175, 0x7fffec, 23);
addChar(176, 0x1fffe0, 21);
addChar(177, 0x1fffe1, 21);
addChar(178, 0x3fffe0, 22);
addChar(179, 0x1fffe2, 21);
addChar(180, 0x7fffed, 23);
addChar(181, 0x3fffe1, 22);
addChar(182, 0x7fffee, 23);
addChar(183, 0x7fffef, 23);
addChar(184, 0xfffea, 20);
addChar(185, 0x3fffe2, 22);
addChar(186, 0x3fffe3, 22);
addChar(187, 0x3fffe4, 22);
addChar(188, 0x7ffff0, 23);
addChar(189, 0x3fffe5, 22);
addChar(190, 0x3fffe6, 22);
addChar(191, 0x7ffff1, 23);
addChar(192, 0x3ffffe0, 26);
addChar(193, 0x3ffffe1, 26);
addChar(194, 0xfffeb, 20);
addChar(195, 0x7fff1, 19);
addChar(196, 0x3fffe7, 22);
addChar(197, 0x7ffff2, 23);
addChar(198, 0x3fffe8, 22);
addChar(199, 0x1ffffec, 25);
addChar(200, 0x3ffffe2, 26);
addChar(201, 0x3ffffe3, 26);
addChar(202, 0x3ffffe4, 26);
addChar(203, 0x7ffffde, 27);
addChar(204, 0x7ffffdf, 27);
addChar(205, 0x3ffffe5, 26);
addChar(206, 0xfffff1, 24);
addChar(207, 0x1ffffed, 25);
addChar(208, 0x7fff2, 19);
addChar(209, 0x1fffe3, 21);
addChar(210, 0x3ffffe6, 26);
addChar(211, 0x7ffffe0, 27);
addChar(212, 0x7ffffe1, 27);
addChar(213, 0x3ffffe7, 26);
addChar(214, 0x7ffffe2, 27);
addChar(215, 0xfffff2, 24);
addChar(216, 0x1fffe4, 21);
addChar(217, 0x1fffe5, 21);
addChar(218, 0x3ffffe8, 26);
addChar(219, 0x3ffffe9, 26);
addChar(220, 0xffffffd, 28);
addChar(221, 0x7ffffe3, 27);
addChar(222, 0x7ffffe4, 27);
addChar(223, 0x7ffffe5, 27);
addChar(224, 0xfffec, 20);
addChar(225, 0xfffff3, 24);
addChar(226, 0xfffed, 20);
addChar(227, 0x1fffe6, 21);
addChar(228, 0x3fffe9, 22);
addChar(229, 0x1fffe7, 21);
addChar(230, 0x1fffe8, 21);
addChar(231, 0x7ffff3, 23);
addChar(232, 0x3fffea, 22);
addChar(233, 0x3fffeb, 22);
addChar(234, 0x1ffffee, 25);
addChar(235, 0x1ffffef, 25);
addChar(236, 0xfffff4, 24);
addChar(237, 0xfffff5, 24);
addChar(238, 0x3ffffea, 26);
addChar(239, 0x7ffff4, 23);
addChar(240, 0x3ffffeb, 26);
addChar(241, 0x7ffffe6, 27);
addChar(242, 0x3ffffec, 26);
addChar(243, 0x3ffffed, 26);
addChar(244, 0x7ffffe7, 27);
addChar(245, 0x7ffffe8, 27);
addChar(246, 0x7ffffe9, 27);
addChar(247, 0x7ffffea, 27);
addChar(248, 0x7ffffeb, 27);
addChar(249, 0xffffffe, 28);
addChar(250, 0x7ffffec, 27);
addChar(251, 0x7ffffed, 27);
addChar(252, 0x7ffffee, 27);
addChar(253, 0x7ffffef, 27);
addChar(254, 0x7fffff0, 27);
addChar(255, 0x3ffffee, 26);
addEOS (256, EOS.code, EOS.length);
// @formatter:on
}
public String from(Buffer source) {
return from(source, true);
}
String from(Buffer source, boolean reportEOS) {
// TODO: reuse? (objects creation, performance)
StringBuilder result = new StringBuilder();
Node curr = root;
int len = 0;
while(source.hasRemaining()) {
int d = source.get();
for (int p = 0x80; p != 0; p = p >> 1) {
curr = curr.getChild(p & d);
len++;
if (curr.isLeaf()) {
if (reportEOS && curr.isEOSPath) {
throw new IllegalArgumentException("Encountered EOS");
}
len = 0;
result.append(curr.getChar());
curr = root;
}
}
}
if (curr.isLeaf()) {
return result.toString();
}
if (curr.isEOSPath) {
if (len > 7) {
throw new IllegalArgumentException(
"Padding is too long (len=" + len + ") " +
"or unexpected end of data");
} else {
return result.toString();
}
} else {
throw new IllegalArgumentException(
"Not a EOS prefix padding or unexpected end of data");
}
}
public int lengthOf(final byte[] value,
final int off, final int len) {
int rsltLen = 0;
final int end = off + len;
for (int i = off; i < end; i++) {
rsltLen += codeOf(value[i]).length;
}
return (rsltLen >> 3) + ((rsltLen & 7) != 0 ? 1 : 0);
}
public int lengthOf(final String value) {
int rsltLen = 0;
final int length = value.length();
for (int i = 0; i < length; i++) {
rsltLen += codeOf((byte) value.charAt(i)).length;
}
return (rsltLen >> 3) + ((rsltLen & 7) != 0 ? 1 : 0);
}
public void to(OutputStream destination, byte[] value, int off, int len)
throws IOException {
int a = 8; // how much space left in 'b' to append to (available)
int b = 0; // the byte to write next (8 least significant bits)
final int end = off + len;
for (int i = off; i < end; i++) {
Code desc = codeOf(value[i]);
int code = desc.code;
int r = desc.length; // remaining number code bits to write
while (r > 0) {
if (r < a) {
b |= (code << (a - r));
a -= r;
r = 0;
} else {
b |= (code >>> (r - a));
destination.write((byte) b);
code &= (1 << (r - a)) - 1; // keep only (r-a) lower bits
r -= a;
b = 0;
a = 8;
}
}
}
if (a < 8) { // have to pad with EOS
destination.write((byte) (b | ((1 << a) - 1)));
}
}
public void to(final OutputStream destination, final String value)
throws IOException {
int a = 8; // how much space left in 'b' to append to (available)
int b = 0; // the byte to write next (8 least significant bits)
final int len = value.length();
for (int i = 0; i < len; i++) {
Code desc = codeOf((byte) value.charAt(i));
int code = desc.code;
int r = desc.length; // remaining number code bits to write
while (r > 0) {
if (r < a) {
b |= (code << (a - r));
a -= r;
r = 0;
} else {
b |= (code >>> (r - a));
destination.write((byte) b);
code &= (1 << (r - a)) - 1; // keep only (r-a) lower bits
r -= a;
b = 0;
a = 8;
}
}
}
if (a < 8) { // have to pad with EOS
destination.write((byte) (b | ((1 << a) - 1)));
}
}
private void addChar(int c, int code, int bitLength) {
addLeaf(c, code, bitLength, false);
codes[c] = new Code(code, bitLength);
}
private void addEOS(int c, int code, int bitLength) {
addLeaf(c, code, bitLength, true);
codes[c] = new Code(code, bitLength);
}
private void addLeaf(int c, int code, int bitLength, boolean isEOS) {
if (bitLength < 1)
throw new IllegalArgumentException("bitLength < 1");
Node curr = root;
for (int p = 1 << bitLength - 1; p != 0 && !curr.isLeaf(); p = p >> 1) {
curr.isEOSPath |= isEOS; // if it's already true,
// it can't become false
curr = curr.addChildIfAbsent(p & code);
}
curr.isEOSPath |= isEOS; // the last one needs to have this property
// as well
if (curr.isLeaf())
throw new IllegalStateException("Specified code is already taken");
curr.setChar((char) c);
}
private Code codeOf(byte c) {
return codes[c];
}
//
// for debugging/testing purposes
//
Node getRoot() {
return root;
}
//
// Guarantees:
//
// if (isLeaf() == true) => getChar() is a legal call
// if (isLeaf() == false) => getChild(i) is a legal call (though it can
// return null)
//
static class Node {
Node left;
Node right;
boolean isEOSPath;
boolean charIsSet;
char c;
Node getChild(int selector) {
if (isLeaf()) {
throw new IllegalStateException("This is a leaf node");
}
Node result = selector == 0 ? left : right;
if (result == null)
throw new IllegalStateException(format(
"Node doesn't have a child (selector=%s)", selector));
return result;
}
boolean isLeaf() {
return charIsSet;
}
char getChar() {
if (!isLeaf())
throw new IllegalStateException("This node is not a leaf node");
return c;
}
void setChar(char c) {
if (charIsSet) {
throw new IllegalStateException(
"This node has been taken already");
}
if (left != null || right != null) {
throw new IllegalStateException("The node cannot be made "
+ "a leaf as it's already has a child");
}
this.c = c;
charIsSet = true;
}
Node addChildIfAbsent(int i) {
if (charIsSet)
throw new IllegalStateException();
Node child;
if (i == 0) {
if ((child = left) == null)
child = left = new Node();
} else {
if ((child = right) == null)
child = right = new Node();
}
return child;
}
@Override
public String toString() {
if (isLeaf()) {
if (isEOSPath) {
return "EOS";
} else {
return format("char: (%3s) '%s'", (int) c, c);
}
}
return "/\\";
}
}
private static class Code {
final int code;
final int length;
private Code(int code, int length) {
this.code = code;
this.length = length;
}
public int getCode() {
return code;
}
public int getLength() {
return length;
}
@Override
public String toString() {
long p = 1 << length;
return Long.toBinaryString(code + p).substring(1)
+ ", length=" + length;
}
}
}
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