--- a/src/java.net.http/share/classes/jdk/internal/net/http/hpack/Huffman.java Tue May 01 10:03:01 2018 +0100
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/hpack/Huffman.java Tue May 01 19:14:46 2018 +0100
@@ -27,655 +27,60 @@
import java.io.IOException;
import java.nio.ByteBuffer;
-import static java.lang.String.format;
-
/**
- * Huffman coding table.
- *
- * <p> Instances of this class are safe for use by multiple threads.
+ * Huffman coding.
*
* @since 9
*/
public final class Huffman {
- // TODO: check if reset is done in both reader and writer
-
- static final class Reader {
-
- private Node curr; // position in the trie
- private int len; // length of the path from the root to 'curr'
- private int p; // byte probe
+ public interface Reader {
- {
- reset();
- }
-
- public void read(ByteBuffer source,
- Appendable destination,
- boolean isLast) throws IOException {
- read(source, destination, true, isLast);
- }
-
- // Takes 'isLast' rather than returns whether the reading is done or
- // not, for more informative exceptions.
void read(ByteBuffer source,
Appendable destination,
- boolean reportEOS, /* reportEOS is exposed for tests */
- boolean isLast) throws IOException {
- Node c = curr;
- int l = len;
- /*
- Since ByteBuffer is itself stateful, its position is
- remembered here NOT as a part of Reader's state,
- but to set it back in the case of a failure
- */
- int pos = source.position();
-
- while (source.hasRemaining()) {
- int d = source.get();
- for (; p != 0; p >>= 1) {
- c = c.getChild(p & d);
- l++;
- if (c.isLeaf()) {
- if (reportEOS && c.isEOSPath) {
- throw new IOException("Encountered EOS");
- }
- char ch;
- try {
- ch = c.getChar();
- } catch (IllegalStateException e) {
- source.position(pos); // do we need this?
- throw new IOException(e);
- }
- try {
- destination.append(ch);
- } catch (IOException e) {
- source.position(pos); // do we need this?
- throw e;
- }
- c = INSTANCE.root;
- l = 0;
- }
- curr = c;
- len = l;
- }
- resetProbe();
- pos++;
- }
- if (!isLast) {
- return; // it's too early to jump to any conclusions, let's wait
- }
- if (c.isLeaf()) {
- return; // it's perfectly ok, no extra padding bits
- }
- if (c.isEOSPath && len <= 7) {
- return; // it's ok, some extra padding bits
- }
- if (c.isEOSPath) {
- throw new IOException(
- "Padding is too long (len=" + len + ") " +
- "or unexpected end of data");
- }
- throw new IOException(
- "Not a EOS prefix padding or unexpected end of data");
- }
-
- public void reset() {
- curr = INSTANCE.root;
- len = 0;
- resetProbe();
- }
-
- private void resetProbe() {
- p = 0x80;
- }
- }
+ boolean isLast) throws IOException;
- static final class Writer {
-
- private int pos; // position in 'source'
- private int avail = 8; // number of least significant bits available in 'curr'
- private int curr; // next byte to put to the destination
- private int rem; // number of least significant bits in 'code' yet to be processed
- private int code; // current code being written
-
- private CharSequence source;
- private int end;
-
- public Writer from(CharSequence input, int start, int end) {
- if (start < 0 || end < 0 || end > input.length() || start > end) {
- throw new IndexOutOfBoundsException(
- String.format("input.length()=%s, start=%s, end=%s",
- input.length(), start, end));
- }
- pos = start;
- this.end = end;
- this.source = input;
- return this;
- }
-
- public boolean write(ByteBuffer destination) {
- for (; pos < end; pos++) {
- if (rem == 0) {
- Code desc = INSTANCE.codeOf(source.charAt(pos));
- rem = desc.length;
- code = desc.code;
- }
- while (rem > 0) {
- if (rem < avail) {
- curr |= (code << (avail - rem));
- avail -= rem;
- rem = 0;
- } else {
- int c = (curr | (code >>> (rem - avail)));
- if (destination.hasRemaining()) {
- destination.put((byte) c);
- } else {
- return false;
- }
- curr = c;
- code <<= (32 - rem + avail); // throw written bits off the cliff (is this Sparta?)
- code >>>= (32 - rem + avail); // return to the position
- rem -= avail;
- curr = 0;
- avail = 8;
- }
- }
- }
-
- if (avail < 8) { // have to pad
- if (destination.hasRemaining()) {
- destination.put((byte) (curr | (INSTANCE.EOS.code >>> (INSTANCE.EOS.length - avail))));
- avail = 8;
- } else {
- return false;
- }
- }
-
- return true;
- }
-
- public Writer reset() {
- source = null;
- end = -1;
- pos = -1;
- avail = 8;
- curr = 0;
- code = 0;
- return this;
- }
+ /**
+ * Brings this reader to the state it had upon construction.
+ */
+ void reset();
}
- /**
- * Shared instance.
- */
- public static final Huffman INSTANCE = new Huffman();
+ public interface Writer {
+
+ Writer from(CharSequence input, int start, int end);
+
+ boolean write(ByteBuffer destination);
- 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"; }
- };
+ /**
+ * Brings this writer to the state it had upon construction.
+ *
+ * @return this writer
+ */
+ Writer reset();
- // TODO: consider builder and immutable trie
- private Huffman() {
- // @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
- }
+ /**
+ * Calculates the number of bytes required to represent a subsequence of
+ * the given {@code CharSequence} using the Huffman coding.
+ *
+ * @param value
+ * characters
+ * @param start
+ * the start index, inclusive
+ * @param end
+ * the end index, exclusive
+ *
+ * @return number of bytes
+ * @throws NullPointerException
+ * if the value is null
+ * @throws IndexOutOfBoundsException
+ * if any invocation of {@code value.charAt(i)}, where
+ * {@code start <= i < end}, throws an IndexOutOfBoundsException
+ */
+ int lengthOf(CharSequence value, int start, int end);
-
- /**
- * Calculates the number of bytes required to represent the given {@code
- * CharSequence} with the Huffman coding.
- *
- * @param value
- * characters
- *
- * @return number of bytes
- *
- * @throws NullPointerException
- * if the value is null
- */
- public int lengthOf(CharSequence value) {
- return lengthOf(value, 0, value.length());
- }
-
- /**
- * Calculates the number of bytes required to represent a subsequence of the
- * given {@code CharSequence} with the Huffman coding.
- *
- * @param value
- * characters
- * @param start
- * the start index, inclusive
- * @param end
- * the end index, exclusive
- *
- * @return number of bytes
- *
- * @throws NullPointerException
- * if the value is null
- * @throws IndexOutOfBoundsException
- * if any invocation of {@code value.charAt(i)}, where
- * {@code start <= i < end} would throw an IndexOutOfBoundsException
- */
- public int lengthOf(CharSequence value, int start, int end) {
- int len = 0;
- for (int i = start; i < end; i++) {
- char c = value.charAt(i);
- len += INSTANCE.codeOf(c).length;
- }
- // Integer division with ceiling, assumption:
- assert (len / 8 + (len % 8 != 0 ? 1 : 0)) == (len + 7) / 8 : len;
- return (len + 7) / 8;
- }
-
- 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(char c) {
- if (c > 255) {
- throw new IllegalArgumentException("char=" + ((int) 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("The node cannot have a child "
- + "as it's already a leaf node");
- }
- 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 "/\\";
- }
- }
-
- // TODO: value-based class?
- // FIXME: can we re-use Node instead of this class?
- private static final 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;
+ default int lengthOf(CharSequence value) {
+ return lengthOf(value, 0, value.length());
}
}
}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/hpack/NaiveHuffman.java Tue May 01 19:14:46 2018 +0100
@@ -0,0 +1,691 @@
+/*
+ * Copyright (c) 2014, 2018, 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package jdk.internal.net.http.hpack;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+import static java.lang.String.format;
+
+/**
+ * Huffman coding table.
+ *
+ * <p> Instances of this class are safe for use by multiple threads.
+ *
+ * @since 9
+ */
+public final class NaiveHuffman {
+
+ // TODO: check if reset is done in both reader and writer
+
+ static final class Reader implements Huffman.Reader {
+
+ private Node curr; // position in the trie
+ private int len; // length of the path from the root to 'curr'
+ private int p; // byte probe
+
+ {
+ reset();
+ }
+
+ @Override
+ public void read(ByteBuffer source,
+ Appendable destination,
+ boolean isLast) throws IOException {
+ read(source, destination, true, isLast);
+ }
+
+ // Takes 'isLast' rather than returns whether the reading is done or
+ // not, for more informative exceptions.
+ void read(ByteBuffer source,
+ Appendable destination,
+ boolean reportEOS, /* reportEOS is exposed for tests */
+ boolean isLast) throws IOException {
+ Node c = curr;
+ int l = len;
+ /*
+ Since ByteBuffer is itself stateful, its position is
+ remembered here NOT as a part of Reader's state,
+ but to set it back in the case of a failure
+ */
+ int pos = source.position();
+
+ while (source.hasRemaining()) {
+ int d = source.get();
+ for (; p != 0; p >>= 1) {
+ c = c.getChild(p & d);
+ l++;
+ if (c.isLeaf()) {
+ if (reportEOS && c.isEOSPath) {
+ throw new IOException("Encountered EOS");
+ }
+ char ch;
+ try {
+ ch = c.getChar();
+ } catch (IllegalStateException e) {
+ source.position(pos); // do we need this?
+ throw new IOException(e);
+ }
+ try {
+ destination.append(ch);
+ } catch (IOException e) {
+ source.position(pos); // do we need this?
+ throw e;
+ }
+ c = INSTANCE.root;
+ l = 0;
+ }
+ curr = c;
+ len = l;
+ }
+ resetProbe();
+ pos++;
+ }
+ if (!isLast) {
+ return; // it's too early to jump to any conclusions, let's wait
+ }
+ if (c.isLeaf()) {
+ return; // it's perfectly ok, no extra padding bits
+ }
+ if (c.isEOSPath && len <= 7) {
+ return; // it's ok, some extra padding bits
+ }
+ if (c.isEOSPath) {
+ throw new IOException(
+ "Padding is too long (len=" + len + ") " +
+ "or unexpected end of data");
+ }
+ throw new IOException(
+ "Not a EOS prefix padding or unexpected end of data");
+ }
+
+ @Override
+ public void reset() {
+ curr = INSTANCE.root;
+ len = 0;
+ resetProbe();
+ }
+
+ private void resetProbe() {
+ p = 0x80;
+ }
+ }
+
+ static final class Writer implements Huffman.Writer {
+
+ private int pos; // position in 'source'
+ private int avail = 8; // number of least significant bits available in 'curr'
+ private int curr; // next byte to put to the destination
+ private int rem; // number of least significant bits in 'code' yet to be processed
+ private int code; // current code being written
+
+ private CharSequence source;
+ private int end;
+
+ @Override
+ public Writer from(CharSequence input, int start, int end) {
+ if (start < 0 || end < 0 || end > input.length() || start > end) {
+ throw new IndexOutOfBoundsException(
+ String.format("input.length()=%s, start=%s, end=%s",
+ input.length(), start, end));
+ }
+ pos = start;
+ this.end = end;
+ this.source = input;
+ return this;
+ }
+
+ @Override
+ public boolean write(ByteBuffer destination) {
+ for (; pos < end; pos++) {
+ if (rem == 0) {
+ Code desc = INSTANCE.codeOf(source.charAt(pos));
+ rem = desc.length;
+ code = desc.code;
+ }
+ while (rem > 0) {
+ if (rem < avail) {
+ curr |= (code << (avail - rem));
+ avail -= rem;
+ rem = 0;
+ } else {
+ int c = (curr | (code >>> (rem - avail)));
+ if (destination.hasRemaining()) {
+ destination.put((byte) c);
+ } else {
+ return false;
+ }
+ curr = c;
+ code <<= (32 - rem + avail); // throw written bits off the cliff (is this Sparta?)
+ code >>>= (32 - rem + avail); // return to the position
+ rem -= avail;
+ curr = 0;
+ avail = 8;
+ }
+ }
+ }
+
+ if (avail < 8) { // have to pad
+ if (destination.hasRemaining()) {
+ destination.put((byte) (curr | (INSTANCE.EOS.code >>> (INSTANCE.EOS.length - avail))));
+ avail = 8;
+ } else {
+ return false;
+ }
+ }
+
+ return true;
+ }
+
+ @Override
+ public Writer reset() {
+ source = null;
+ end = -1;
+ pos = -1;
+ avail = 8;
+ curr = 0;
+ code = 0;
+ return this;
+ }
+
+ @Override
+ public int lengthOf(CharSequence value, int start, int end) {
+ return INSTANCE.lengthOf(value, start, end);
+ }
+ }
+
+ /**
+ * Shared instance.
+ */
+ public static final NaiveHuffman INSTANCE = new NaiveHuffman();
+
+ 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"; }
+ };
+
+ // TODO: consider builder and immutable trie
+ private NaiveHuffman() {
+ // @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
+ }
+
+
+ /**
+ * Calculates the number of bytes required to represent the given {@code
+ * CharSequence} with the Huffman coding.
+ *
+ * @param value
+ * characters
+ *
+ * @return number of bytes
+ *
+ * @throws NullPointerException
+ * if the value is null
+ */
+ public int lengthOf(CharSequence value) {
+ return lengthOf(value, 0, value.length());
+ }
+
+ /**
+ * Calculates the number of bytes required to represent a subsequence of the
+ * given {@code CharSequence} with the Huffman coding.
+ *
+ * @param value
+ * characters
+ * @param start
+ * the start index, inclusive
+ * @param end
+ * the end index, exclusive
+ *
+ * @return number of bytes
+ *
+ * @throws NullPointerException
+ * if the value is null
+ * @throws IndexOutOfBoundsException
+ * if any invocation of {@code value.charAt(i)}, where
+ * {@code start <= i < end} would throw an IndexOutOfBoundsException
+ */
+ public int lengthOf(CharSequence value, int start, int end) {
+ int len = 0;
+ for (int i = start; i < end; i++) {
+ char c = value.charAt(i);
+ len += INSTANCE.codeOf(c).length;
+ }
+ // Integer division with ceiling, assumption:
+ assert (len / 8 + (len % 8 != 0 ? 1 : 0)) == (len + 7) / 8 : len;
+ return (len + 7) / 8;
+ }
+
+ 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(char c) {
+ if (c > 255) {
+ throw new IllegalArgumentException("char=" + ((int) 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("The node cannot have a child "
+ + "as it's already a leaf node");
+ }
+ 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 "/\\";
+ }
+ }
+
+ // TODO: value-based class?
+ // FIXME: can we re-use Node instead of this class?
+ private static final 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;
+ }
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/hpack/QuickHuffman.java Tue May 01 19:14:46 2018 +0100
@@ -0,0 +1,826 @@
+/*
+ * Copyright (c) 2018, 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.internal.net.http.hpack;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+import java.util.Objects;
+
+public final class QuickHuffman {
+
+ /*
+ * Huffman codes for encoding.
+ *
+ * EOS will never be matched, since there is no symbol for it, thus no need
+ * to store it in the array. Thus, the length of the array is 256, not 257.
+ * Code information for each character is encoded as follows:
+ *
+ * MSB LSB
+ * +----------------+----------------+
+ * |~code | length~|
+ * +----------------+----------------+
+ * |<----- 32 ----->|<----- 32 ----->|
+ * |<------------- 64 -------------->|
+ *
+ * The leftmost 32 bits hold the code value. This value is aligned left
+ * (or MSB). The rightmost 32 bits hold the length of the code value.
+ * This length is aligned right (or LSB).
+ */
+ private static final long[] codes = new long[256];
+
+ private static long codeValueOf(char c) {
+ return codes[c] & 0xffffffff00000000L;
+ }
+
+ private static long codeLengthOf(char c) {
+ return codes[c] & 0x00000000ffffffffL;
+ }
+
+ private static final int EOS_LENGTH = 30;
+ private static final int EOS_LSB = 0x3fffffff;
+ private static final long EOS_MSB = EOS_LSB << (64 - EOS_LENGTH);
+
+ /*
+ * Huffman codes for decoding.
+ *
+ * Root node contains 257 descendant nodes, including EOS.
+ */
+ private static final Node root;
+
+ static {
+ TemporaryNode tmpRoot = new TemporaryNode();
+ addChar(tmpRoot, 0, 0x1ff8, 13);
+ addChar(tmpRoot, 1, 0x7fffd8, 23);
+ addChar(tmpRoot, 2, 0xfffffe2, 28);
+ addChar(tmpRoot, 3, 0xfffffe3, 28);
+ addChar(tmpRoot, 4, 0xfffffe4, 28);
+ addChar(tmpRoot, 5, 0xfffffe5, 28);
+ addChar(tmpRoot, 6, 0xfffffe6, 28);
+ addChar(tmpRoot, 7, 0xfffffe7, 28);
+ addChar(tmpRoot, 8, 0xfffffe8, 28);
+ addChar(tmpRoot, 9, 0xffffea, 24);
+ addChar(tmpRoot, 10, 0x3ffffffc, 30);
+ addChar(tmpRoot, 11, 0xfffffe9, 28);
+ addChar(tmpRoot, 12, 0xfffffea, 28);
+ addChar(tmpRoot, 13, 0x3ffffffd, 30);
+ addChar(tmpRoot, 14, 0xfffffeb, 28);
+ addChar(tmpRoot, 15, 0xfffffec, 28);
+ addChar(tmpRoot, 16, 0xfffffed, 28);
+ addChar(tmpRoot, 17, 0xfffffee, 28);
+ addChar(tmpRoot, 18, 0xfffffef, 28);
+ addChar(tmpRoot, 19, 0xffffff0, 28);
+ addChar(tmpRoot, 20, 0xffffff1, 28);
+ addChar(tmpRoot, 21, 0xffffff2, 28);
+ addChar(tmpRoot, 22, 0x3ffffffe, 30);
+ addChar(tmpRoot, 23, 0xffffff3, 28);
+ addChar(tmpRoot, 24, 0xffffff4, 28);
+ addChar(tmpRoot, 25, 0xffffff5, 28);
+ addChar(tmpRoot, 26, 0xffffff6, 28);
+ addChar(tmpRoot, 27, 0xffffff7, 28);
+ addChar(tmpRoot, 28, 0xffffff8, 28);
+ addChar(tmpRoot, 29, 0xffffff9, 28);
+ addChar(tmpRoot, 30, 0xffffffa, 28);
+ addChar(tmpRoot, 31, 0xffffffb, 28);
+ addChar(tmpRoot, 32, 0x14, 6);
+ addChar(tmpRoot, 33, 0x3f8, 10);
+ addChar(tmpRoot, 34, 0x3f9, 10);
+ addChar(tmpRoot, 35, 0xffa, 12);
+ addChar(tmpRoot, 36, 0x1ff9, 13);
+ addChar(tmpRoot, 37, 0x15, 6);
+ addChar(tmpRoot, 38, 0xf8, 8);
+ addChar(tmpRoot, 39, 0x7fa, 11);
+ addChar(tmpRoot, 40, 0x3fa, 10);
+ addChar(tmpRoot, 41, 0x3fb, 10);
+ addChar(tmpRoot, 42, 0xf9, 8);
+ addChar(tmpRoot, 43, 0x7fb, 11);
+ addChar(tmpRoot, 44, 0xfa, 8);
+ addChar(tmpRoot, 45, 0x16, 6);
+ addChar(tmpRoot, 46, 0x17, 6);
+ addChar(tmpRoot, 47, 0x18, 6);
+ addChar(tmpRoot, 48, 0x0, 5);
+ addChar(tmpRoot, 49, 0x1, 5);
+ addChar(tmpRoot, 50, 0x2, 5);
+ addChar(tmpRoot, 51, 0x19, 6);
+ addChar(tmpRoot, 52, 0x1a, 6);
+ addChar(tmpRoot, 53, 0x1b, 6);
+ addChar(tmpRoot, 54, 0x1c, 6);
+ addChar(tmpRoot, 55, 0x1d, 6);
+ addChar(tmpRoot, 56, 0x1e, 6);
+ addChar(tmpRoot, 57, 0x1f, 6);
+ addChar(tmpRoot, 58, 0x5c, 7);
+ addChar(tmpRoot, 59, 0xfb, 8);
+ addChar(tmpRoot, 60, 0x7ffc, 15);
+ addChar(tmpRoot, 61, 0x20, 6);
+ addChar(tmpRoot, 62, 0xffb, 12);
+ addChar(tmpRoot, 63, 0x3fc, 10);
+ addChar(tmpRoot, 64, 0x1ffa, 13);
+ addChar(tmpRoot, 65, 0x21, 6);
+ addChar(tmpRoot, 66, 0x5d, 7);
+ addChar(tmpRoot, 67, 0x5e, 7);
+ addChar(tmpRoot, 68, 0x5f, 7);
+ addChar(tmpRoot, 69, 0x60, 7);
+ addChar(tmpRoot, 70, 0x61, 7);
+ addChar(tmpRoot, 71, 0x62, 7);
+ addChar(tmpRoot, 72, 0x63, 7);
+ addChar(tmpRoot, 73, 0x64, 7);
+ addChar(tmpRoot, 74, 0x65, 7);
+ addChar(tmpRoot, 75, 0x66, 7);
+ addChar(tmpRoot, 76, 0x67, 7);
+ addChar(tmpRoot, 77, 0x68, 7);
+ addChar(tmpRoot, 78, 0x69, 7);
+ addChar(tmpRoot, 79, 0x6a, 7);
+ addChar(tmpRoot, 80, 0x6b, 7);
+ addChar(tmpRoot, 81, 0x6c, 7);
+ addChar(tmpRoot, 82, 0x6d, 7);
+ addChar(tmpRoot, 83, 0x6e, 7);
+ addChar(tmpRoot, 84, 0x6f, 7);
+ addChar(tmpRoot, 85, 0x70, 7);
+ addChar(tmpRoot, 86, 0x71, 7);
+ addChar(tmpRoot, 87, 0x72, 7);
+ addChar(tmpRoot, 88, 0xfc, 8);
+ addChar(tmpRoot, 89, 0x73, 7);
+ addChar(tmpRoot, 90, 0xfd, 8);
+ addChar(tmpRoot, 91, 0x1ffb, 13);
+ addChar(tmpRoot, 92, 0x7fff0, 19);
+ addChar(tmpRoot, 93, 0x1ffc, 13);
+ addChar(tmpRoot, 94, 0x3ffc, 14);
+ addChar(tmpRoot, 95, 0x22, 6);
+ addChar(tmpRoot, 96, 0x7ffd, 15);
+ addChar(tmpRoot, 97, 0x3, 5);
+ addChar(tmpRoot, 98, 0x23, 6);
+ addChar(tmpRoot, 99, 0x4, 5);
+ addChar(tmpRoot, 100, 0x24, 6);
+ addChar(tmpRoot, 101, 0x5, 5);
+ addChar(tmpRoot, 102, 0x25, 6);
+ addChar(tmpRoot, 103, 0x26, 6);
+ addChar(tmpRoot, 104, 0x27, 6);
+ addChar(tmpRoot, 105, 0x6, 5);
+ addChar(tmpRoot, 106, 0x74, 7);
+ addChar(tmpRoot, 107, 0x75, 7);
+ addChar(tmpRoot, 108, 0x28, 6);
+ addChar(tmpRoot, 109, 0x29, 6);
+ addChar(tmpRoot, 110, 0x2a, 6);
+ addChar(tmpRoot, 111, 0x7, 5);
+ addChar(tmpRoot, 112, 0x2b, 6);
+ addChar(tmpRoot, 113, 0x76, 7);
+ addChar(tmpRoot, 114, 0x2c, 6);
+ addChar(tmpRoot, 115, 0x8, 5);
+ addChar(tmpRoot, 116, 0x9, 5);
+ addChar(tmpRoot, 117, 0x2d, 6);
+ addChar(tmpRoot, 118, 0x77, 7);
+ addChar(tmpRoot, 119, 0x78, 7);
+ addChar(tmpRoot, 120, 0x79, 7);
+ addChar(tmpRoot, 121, 0x7a, 7);
+ addChar(tmpRoot, 122, 0x7b, 7);
+ addChar(tmpRoot, 123, 0x7ffe, 15);
+ addChar(tmpRoot, 124, 0x7fc, 11);
+ addChar(tmpRoot, 125, 0x3ffd, 14);
+ addChar(tmpRoot, 126, 0x1ffd, 13);
+ addChar(tmpRoot, 127, 0xffffffc, 28);
+ addChar(tmpRoot, 128, 0xfffe6, 20);
+ addChar(tmpRoot, 129, 0x3fffd2, 22);
+ addChar(tmpRoot, 130, 0xfffe7, 20);
+ addChar(tmpRoot, 131, 0xfffe8, 20);
+ addChar(tmpRoot, 132, 0x3fffd3, 22);
+ addChar(tmpRoot, 133, 0x3fffd4, 22);
+ addChar(tmpRoot, 134, 0x3fffd5, 22);
+ addChar(tmpRoot, 135, 0x7fffd9, 23);
+ addChar(tmpRoot, 136, 0x3fffd6, 22);
+ addChar(tmpRoot, 137, 0x7fffda, 23);
+ addChar(tmpRoot, 138, 0x7fffdb, 23);
+ addChar(tmpRoot, 139, 0x7fffdc, 23);
+ addChar(tmpRoot, 140, 0x7fffdd, 23);
+ addChar(tmpRoot, 141, 0x7fffde, 23);
+ addChar(tmpRoot, 142, 0xffffeb, 24);
+ addChar(tmpRoot, 143, 0x7fffdf, 23);
+ addChar(tmpRoot, 144, 0xffffec, 24);
+ addChar(tmpRoot, 145, 0xffffed, 24);
+ addChar(tmpRoot, 146, 0x3fffd7, 22);
+ addChar(tmpRoot, 147, 0x7fffe0, 23);
+ addChar(tmpRoot, 148, 0xffffee, 24);
+ addChar(tmpRoot, 149, 0x7fffe1, 23);
+ addChar(tmpRoot, 150, 0x7fffe2, 23);
+ addChar(tmpRoot, 151, 0x7fffe3, 23);
+ addChar(tmpRoot, 152, 0x7fffe4, 23);
+ addChar(tmpRoot, 153, 0x1fffdc, 21);
+ addChar(tmpRoot, 154, 0x3fffd8, 22);
+ addChar(tmpRoot, 155, 0x7fffe5, 23);
+ addChar(tmpRoot, 156, 0x3fffd9, 22);
+ addChar(tmpRoot, 157, 0x7fffe6, 23);
+ addChar(tmpRoot, 158, 0x7fffe7, 23);
+ addChar(tmpRoot, 159, 0xffffef, 24);
+ addChar(tmpRoot, 160, 0x3fffda, 22);
+ addChar(tmpRoot, 161, 0x1fffdd, 21);
+ addChar(tmpRoot, 162, 0xfffe9, 20);
+ addChar(tmpRoot, 163, 0x3fffdb, 22);
+ addChar(tmpRoot, 164, 0x3fffdc, 22);
+ addChar(tmpRoot, 165, 0x7fffe8, 23);
+ addChar(tmpRoot, 166, 0x7fffe9, 23);
+ addChar(tmpRoot, 167, 0x1fffde, 21);
+ addChar(tmpRoot, 168, 0x7fffea, 23);
+ addChar(tmpRoot, 169, 0x3fffdd, 22);
+ addChar(tmpRoot, 170, 0x3fffde, 22);
+ addChar(tmpRoot, 171, 0xfffff0, 24);
+ addChar(tmpRoot, 172, 0x1fffdf, 21);
+ addChar(tmpRoot, 173, 0x3fffdf, 22);
+ addChar(tmpRoot, 174, 0x7fffeb, 23);
+ addChar(tmpRoot, 175, 0x7fffec, 23);
+ addChar(tmpRoot, 176, 0x1fffe0, 21);
+ addChar(tmpRoot, 177, 0x1fffe1, 21);
+ addChar(tmpRoot, 178, 0x3fffe0, 22);
+ addChar(tmpRoot, 179, 0x1fffe2, 21);
+ addChar(tmpRoot, 180, 0x7fffed, 23);
+ addChar(tmpRoot, 181, 0x3fffe1, 22);
+ addChar(tmpRoot, 182, 0x7fffee, 23);
+ addChar(tmpRoot, 183, 0x7fffef, 23);
+ addChar(tmpRoot, 184, 0xfffea, 20);
+ addChar(tmpRoot, 185, 0x3fffe2, 22);
+ addChar(tmpRoot, 186, 0x3fffe3, 22);
+ addChar(tmpRoot, 187, 0x3fffe4, 22);
+ addChar(tmpRoot, 188, 0x7ffff0, 23);
+ addChar(tmpRoot, 189, 0x3fffe5, 22);
+ addChar(tmpRoot, 190, 0x3fffe6, 22);
+ addChar(tmpRoot, 191, 0x7ffff1, 23);
+ addChar(tmpRoot, 192, 0x3ffffe0, 26);
+ addChar(tmpRoot, 193, 0x3ffffe1, 26);
+ addChar(tmpRoot, 194, 0xfffeb, 20);
+ addChar(tmpRoot, 195, 0x7fff1, 19);
+ addChar(tmpRoot, 196, 0x3fffe7, 22);
+ addChar(tmpRoot, 197, 0x7ffff2, 23);
+ addChar(tmpRoot, 198, 0x3fffe8, 22);
+ addChar(tmpRoot, 199, 0x1ffffec, 25);
+ addChar(tmpRoot, 200, 0x3ffffe2, 26);
+ addChar(tmpRoot, 201, 0x3ffffe3, 26);
+ addChar(tmpRoot, 202, 0x3ffffe4, 26);
+ addChar(tmpRoot, 203, 0x7ffffde, 27);
+ addChar(tmpRoot, 204, 0x7ffffdf, 27);
+ addChar(tmpRoot, 205, 0x3ffffe5, 26);
+ addChar(tmpRoot, 206, 0xfffff1, 24);
+ addChar(tmpRoot, 207, 0x1ffffed, 25);
+ addChar(tmpRoot, 208, 0x7fff2, 19);
+ addChar(tmpRoot, 209, 0x1fffe3, 21);
+ addChar(tmpRoot, 210, 0x3ffffe6, 26);
+ addChar(tmpRoot, 211, 0x7ffffe0, 27);
+ addChar(tmpRoot, 212, 0x7ffffe1, 27);
+ addChar(tmpRoot, 213, 0x3ffffe7, 26);
+ addChar(tmpRoot, 214, 0x7ffffe2, 27);
+ addChar(tmpRoot, 215, 0xfffff2, 24);
+ addChar(tmpRoot, 216, 0x1fffe4, 21);
+ addChar(tmpRoot, 217, 0x1fffe5, 21);
+ addChar(tmpRoot, 218, 0x3ffffe8, 26);
+ addChar(tmpRoot, 219, 0x3ffffe9, 26);
+ addChar(tmpRoot, 220, 0xffffffd, 28);
+ addChar(tmpRoot, 221, 0x7ffffe3, 27);
+ addChar(tmpRoot, 222, 0x7ffffe4, 27);
+ addChar(tmpRoot, 223, 0x7ffffe5, 27);
+ addChar(tmpRoot, 224, 0xfffec, 20);
+ addChar(tmpRoot, 225, 0xfffff3, 24);
+ addChar(tmpRoot, 226, 0xfffed, 20);
+ addChar(tmpRoot, 227, 0x1fffe6, 21);
+ addChar(tmpRoot, 228, 0x3fffe9, 22);
+ addChar(tmpRoot, 229, 0x1fffe7, 21);
+ addChar(tmpRoot, 230, 0x1fffe8, 21);
+ addChar(tmpRoot, 231, 0x7ffff3, 23);
+ addChar(tmpRoot, 232, 0x3fffea, 22);
+ addChar(tmpRoot, 233, 0x3fffeb, 22);
+ addChar(tmpRoot, 234, 0x1ffffee, 25);
+ addChar(tmpRoot, 235, 0x1ffffef, 25);
+ addChar(tmpRoot, 236, 0xfffff4, 24);
+ addChar(tmpRoot, 237, 0xfffff5, 24);
+ addChar(tmpRoot, 238, 0x3ffffea, 26);
+ addChar(tmpRoot, 239, 0x7ffff4, 23);
+ addChar(tmpRoot, 240, 0x3ffffeb, 26);
+ addChar(tmpRoot, 241, 0x7ffffe6, 27);
+ addChar(tmpRoot, 242, 0x3ffffec, 26);
+ addChar(tmpRoot, 243, 0x3ffffed, 26);
+ addChar(tmpRoot, 244, 0x7ffffe7, 27);
+ addChar(tmpRoot, 245, 0x7ffffe8, 27);
+ addChar(tmpRoot, 246, 0x7ffffe9, 27);
+ addChar(tmpRoot, 247, 0x7ffffea, 27);
+ addChar(tmpRoot, 248, 0x7ffffeb, 27);
+ addChar(tmpRoot, 249, 0xffffffe, 28);
+ addChar(tmpRoot, 250, 0x7ffffec, 27);
+ addChar(tmpRoot, 251, 0x7ffffed, 27);
+ addChar(tmpRoot, 252, 0x7ffffee, 27);
+ addChar(tmpRoot, 253, 0x7ffffef, 27);
+ addChar(tmpRoot, 254, 0x7fffff0, 27);
+ addChar(tmpRoot, 255, 0x3ffffee, 26);
+ addEOS (tmpRoot, 256, EOS_LSB, EOS_LENGTH);
+
+ // The difference in performance can always be checked by not using
+ // the immutable trie:
+ // root = tmpRoot;
+ root = ImmutableNode.copyOf(tmpRoot);
+ }
+
+ private QuickHuffman() { }
+
+ private static void addChar(Node root, int symbol, int code, int bitLength)
+ {
+ addLeaf(root, (char) symbol, code, bitLength, false);
+ long value = ((long) code) << (64 - bitLength); // re-align MSB <- LSB
+ codes[symbol] = value | bitLength;
+ }
+
+ private static void addEOS(Node root, int symbol, int code, int bitLength)
+ {
+ addLeaf(root, (char) symbol, code, bitLength, true);
+ }
+
+ private static void addLeaf(Node root,
+ char symbol,
+ int code,
+ int bitLength,
+ boolean isEOS)
+ {
+ assert 0 < bitLength && bitLength <= 32 : bitLength;
+ Node curr = root;
+ int nBytes = bytesForBits(bitLength);
+ // The number of bits the code needs to be shifted to the left in order
+ // to align with the byte #nBytes boundary:
+ int align = (nBytes << 3) - bitLength;
+ code <<= align;
+ // descend the trie until the last element
+ int l = 0;
+ for (int i = 0, probe = 0xff << ((nBytes - 1) << 3);
+ i < nBytes - 1;
+ i++, probe >>>= 8)
+ {
+ curr.setEOSPath(curr.isEOSPath() | isEOS);
+ int idx = (code & probe) >>> ((nBytes - 1 - i) << 3);
+ curr = curr.getOrCreateChild(idx);
+ curr.setLength(8);
+ l += 8;
+ }
+ // Assign the same char to all byte variants. For example, if the code
+ // and its length are 00011b and 5 respectively (letter 'a') then, in
+ // order to be able to match any byte starting with 00011b prefix,
+ // the following nodes need to be created:
+ //
+ // 00011000b, 00011001b, 00011010b, 00011011b, 00011100b, 00011101b,
+ // 00011110b and 00011111b
+ int idx = code & 0xff;
+ curr.setEOSPath(curr.isEOSPath() | isEOS);
+ for (int i = 0; i < (1 << align); i++) {
+ Node child = curr.getOrCreateChild(idx | i);
+ child.setSymbol(symbol);
+ child.setEOSPath(child.isEOSPath() | isEOS);
+ child.setLength(bitLength - l);
+ }
+ }
+
+ /*
+ * A node in the Huffman trie.
+ */
+ interface Node {
+
+ boolean isEOSPath();
+
+ void setEOSPath(boolean value);
+
+ boolean isLeaf();
+
+ Node getChild(int index);
+
+ Node getOrCreateChild(int index);
+
+ Node[] getChildren();
+
+ char getSymbol();
+
+ void setSymbol(char symbol);
+
+ int getLength();
+
+ void setLength(int value);
+ }
+
+ /*
+ * Mutable nodes used for initial construction of the Huffman trie.
+ * (These nodes are perfectly ok to be used after that.)
+ */
+ static final class TemporaryNode implements Node {
+
+ private char symbol;
+ private boolean eosPath;
+ private TemporaryNode[] children;
+ private int length;
+
+ @Override
+ public TemporaryNode getOrCreateChild(int index) {
+ ensureChildrenExist();
+ if (children[index] == null) {
+ children[index] = new TemporaryNode();
+ }
+ return children[index];
+ }
+
+ private void ensureChildrenExist() {
+ if (children == null) {
+ children = new TemporaryNode[256];
+ }
+ }
+
+ @Override
+ public boolean isLeaf() {
+ return children == null;
+ }
+
+ @Override
+ public boolean isEOSPath() {
+ return eosPath;
+ }
+
+ @Override
+ public void setEOSPath(boolean value) {
+ eosPath = value;
+ }
+
+ @Override
+ public TemporaryNode getChild(int index) {
+ ensureChildrenExist();
+ return children[index];
+ }
+
+ @Override
+ public Node[] getChildren() {
+ if (children == null) {
+ return new Node[0];
+ }
+ return children;
+ }
+
+ @Override
+ public char getSymbol() {
+ return symbol;
+ }
+
+ @Override
+ public int getLength() {
+ return length;
+ }
+
+ @Override
+ public void setSymbol(char value) {
+ this.symbol = value;
+ }
+
+ @Override
+ public void setLength(int value) {
+ this.length = value;
+ }
+ }
+
+ /*
+ * Immutable node used to construct traversal-only Huffman trie.
+ *
+ * Once the trie has been built, the support of modifications is no longer
+ * required. An immutable trie should be used. Not only it will help to
+ * catch possible bugs, but hopefully speedup the traversal operations.
+ */
+ static final class ImmutableNode implements Node {
+
+ private final char symbol;
+ private final boolean eosPath;
+ private final int length;
+ private final List<ImmutableNode> children;
+
+ public static ImmutableNode copyOf(Node node) {
+ if (node.isLeaf()) {
+ return new ImmutableNode(node.getSymbol(), node.isEOSPath(),
+ node.getLength());
+ }
+ Node[] children = node.getChildren();
+ ImmutableNode[] immutableChildren = new ImmutableNode[children.length];
+ for (int i = 0; i < children.length; i++) {
+ immutableChildren[i] = copyOf(children[i]);
+ }
+ return new ImmutableNode(node.isEOSPath(), node.getLength(),
+ immutableChildren);
+ }
+
+ /* Creates a leaf node */
+ private ImmutableNode(char symbol,
+ boolean eosPath,
+ int length) {
+ this.symbol = symbol;
+ this.eosPath = eosPath;
+ this.length = length;
+ this.children = List.of();
+ }
+
+ /* Creates a node with children */
+ private ImmutableNode(boolean eosPath,
+ int length,
+ ImmutableNode[] children)
+ {
+ this.symbol = 0;
+ this.eosPath = eosPath;
+ this.length = length;
+ if (children.length == 0) {
+ throw new IllegalArgumentException();
+ }
+ // A list produced by List.of should not be slower than array for
+ // accessing elements by index, and hopefully use additional
+ // optimizations (e.g. jdk.internal.vm.annotation.Stable)
+ this.children = List.of(children);
+ }
+
+ @Override
+ public boolean isLeaf() {
+ return children.isEmpty();
+ }
+
+ @Override
+ public boolean isEOSPath() {
+ return eosPath;
+ }
+
+ @Override
+ public void setEOSPath(boolean value) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public ImmutableNode getChild(int index) {
+ return children.get(index);
+ }
+
+ @Override
+ public ImmutableNode getOrCreateChild(int index) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public ImmutableNode[] getChildren() {
+ // This method is not expected to be called on an immutable node.
+ // If it is called, it requires some investigation.
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public char getSymbol() {
+ return symbol;
+ }
+
+ @Override
+ public void setSymbol(char symbol) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public int getLength() {
+ return length;
+ }
+
+ @Override
+ public void setLength(int value) {
+ throw new UnsupportedOperationException();
+ }
+ }
+
+ static final class Reader implements Huffman.Reader {
+
+ private Node curr = root; // current position in the trie
+ private long buffer; // bits left from the previous match (aligned to the left, or MSB)
+ private int bufferLen; // number of bits in the buffer
+ private int len; // length (in bits) of path to curr
+ private boolean done;
+
+ @Override
+ public void read(ByteBuffer source,
+ Appendable destination,
+ boolean isLast) throws IOException
+ {
+ read(source, destination, true, isLast);
+ }
+
+ @Override
+ public void reset() {
+ curr = root;
+ len = 0;
+ buffer = 0;
+ bufferLen = 0;
+ done = false;
+ }
+
+ @SuppressWarnings("fallthrough")
+ void read(ByteBuffer source,
+ Appendable destination,
+ boolean reportEOS, /* reportEOS is exposed for tests */
+ boolean isLast) throws IOException
+ {
+ while (!done) {
+ // read as much as possible (up to 8 bytes)
+ int remaining = source.remaining();
+ int nBytes = Math.min((64 - bufferLen) >> 3, remaining);
+ switch (nBytes) {
+ case 0:
+ break;
+ case 3:
+ readByte(source);
+ case 2:
+ readByte(source);
+ case 1:
+ readByte(source);
+ break;
+ case 7:
+ readByte(source);
+ case 6:
+ readByte(source);
+ case 5:
+ readByte(source);
+ case 4:
+ readInt(source);
+ break;
+ case 8:
+ readLong(source);
+ break;
+ default:
+ throw new InternalError(String.valueOf(nBytes));
+ }
+ // write as much as possible
+ while (true) {
+ if (bufferLen < 8) {
+ if (nBytes < remaining) { // read again
+ break;
+ } else if (!isLast) { // exit the method to accept more input
+ return;
+ } else if (bufferLen > 0) { // no more data is expected, pad
+ // (this padding may be done more than once)
+ buffer |= ((0xff00000000000000L >>> bufferLen)
+ & 0xff00000000000000L);
+ // do not update bufferLen, since all those ones are
+ // synthetic and are appended merely for the sake of
+ // lookup
+ } else {
+ done = true;
+ break;
+ }
+ }
+ int idx = (int) (buffer >>> 56);
+ Node node = curr.getChild(idx);
+ if (node == null) { // TODO: TEST
+ throw new IOException("Unexpected byte");
+ }
+ if (node.isLeaf()) {
+ if (node.getLength() > bufferLen) { // matched more than we actually could (because of padding)
+ throw new IOException(
+ "Not a EOS prefix padding or unexpected end of data");
+ }
+ if (reportEOS && node.isEOSPath()) {
+ throw new IOException("Encountered EOS");
+ }
+ destination.append(node.getSymbol());
+ curr = root;
+ len = 0;
+ } else {
+ curr = node;
+ // because of the padding, we can't match more bits than
+ // there are currently in the buffer
+ len += Math.min(bufferLen, node.getLength());
+ }
+ buffer <<= node.getLength();
+ bufferLen -= node.getLength();
+ }
+ if (done && (curr.isEOSPath() && len > 7)) {
+ throw new IOException(
+ "Padding is too long (len=" + len + ") "
+ + "or unexpected end of data");
+ }
+ }
+ }
+
+ private void readLong(ByteBuffer source) {
+ buffer = source.getLong();
+ bufferLen = 64;
+ }
+
+ private void readInt(ByteBuffer source) {
+ long b;
+ b = source.getInt() & 0x00000000ffffffffL;
+ buffer |= (b << (32 - bufferLen));
+ bufferLen += 32;
+ }
+
+ private void readByte(ByteBuffer source) {
+ long b = source.get() & 0x00000000000000ffL;
+ buffer |= (b << (56 - bufferLen));
+ bufferLen += 8;
+ }
+ }
+
+ static final class Writer implements Huffman.Writer {
+
+ private CharSequence source;
+ private boolean padded;
+ private int pos;
+ private int end;
+ private long buffer;
+ private int bufferLen;
+
+ @Override
+ public QuickHuffman.Writer from(CharSequence input, int start, int end) {
+ Objects.checkFromToIndex(start, end, input.length());
+ this.pos = start;
+ this.end = end;
+ this.source = input;
+ return this;
+ }
+
+ @SuppressWarnings("fallthrough")
+ @Override
+ public boolean write(ByteBuffer destination) {
+ while (true) {
+ while (bufferLen < 32 && pos < end) {
+ char c = source.charAt(pos++);
+ buffer |= (codeValueOf(c) >>> bufferLen); // append
+ bufferLen += codeLengthOf(c);
+ }
+ if (bufferLen == 0) {
+ return true;
+ }
+ if (pos >= end && !padded) { // no more chars, pad
+ padded = true;
+ buffer |= (EOS_MSB >>> bufferLen);
+ bufferLen = bytesForBits(bufferLen) << 3;
+ }
+ // The number of bytes that can be written at once
+ // (calculating in bytes, not bits, since
+ // destination.remaining() * 8 might overflow)
+
+ int nBytes = Math.min(bytesForBits(bufferLen), destination.remaining()); // ceil?
+ switch (nBytes) {
+ case 0:
+ return false;
+ case 1:
+ case 2:
+ case 3:
+ destination.put((byte) (buffer >>> 56));
+ buffer <<= 8;
+ bufferLen -= 8;
+ break;
+ default:
+ destination.putInt((int) (buffer >>> 32));
+ buffer <<= 32;
+ bufferLen -= 32;
+ break;
+ }
+ }
+ }
+
+ @Override
+ public QuickHuffman.Writer reset() {
+ source = null;
+ buffer = 0;
+ bufferLen = 0;
+ end = 0;
+ pos = 0;
+ padded = false;
+ return this;
+ }
+
+ @Override
+ public int lengthOf(CharSequence value, int start, int end) {
+ int len = 0;
+ for (int i = start; i < end; i++) {
+ char c = value.charAt(i);
+ len += codeLengthOf(c);
+ }
+ return bytesForBits(len);
+ }
+ }
+
+ /*
+ * Returns the number of bytes the given number of bits constitute.
+ */
+ private static int bytesForBits(int n) {
+ assert (n / 8 + (n % 8 != 0 ? 1 : 0)) == (n + 7) / 8
+ && (n + 7) / 8 == ((n + 7) >> 3) : n;
+ return (n + 7) >> 3;
+ }
+}
--- a/src/java.net.http/share/classes/jdk/internal/net/http/hpack/StringReader.java Tue May 01 10:03:01 2018 +0100
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/hpack/StringReader.java Tue May 01 19:14:46 2018 +0100
@@ -44,7 +44,7 @@
private static final int DONE = 4;
private final IntegerReader intReader = new IntegerReader();
- private final Huffman.Reader huffmanReader = new Huffman.Reader();
+ private final Huffman.Reader huffmanReader = new QuickHuffman.Reader();
private final ISO_8859_1.Reader plainReader = new ISO_8859_1.Reader();
private int state = NEW;
--- a/src/java.net.http/share/classes/jdk/internal/net/http/hpack/StringWriter.java Tue May 01 10:03:01 2018 +0100
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/hpack/StringWriter.java Tue May 01 19:14:46 2018 +0100
@@ -52,7 +52,7 @@
private static final int DONE = 4;
private final IntegerWriter intWriter = new IntegerWriter();
- private final Huffman.Writer huffmanWriter = new Huffman.Writer();
+ private final Huffman.Writer huffmanWriter = new QuickHuffman.Writer();
private final ISO_8859_1.Writer plainWriter = new ISO_8859_1.Writer();
private int state = NEW;
@@ -76,7 +76,7 @@
intWriter.configure(end - start, 7, 0b0000_0000);
} else {
huffmanWriter.from(input, start, end);
- intWriter.configure(Huffman.INSTANCE.lengthOf(input, start, end),
+ intWriter.configure(huffmanWriter.lengthOf(input, start, end),
7, 0b1000_0000);
}
--- a/test/jdk/java/net/httpclient/http2/java.net.http/jdk/internal/net/http/hpack/DecoderTest.java Tue May 01 10:03:01 2018 +0100
+++ b/test/jdk/java/net/httpclient/http2/java.net.http/jdk/internal/net/http/hpack/DecoderTest.java Tue May 01 19:14:46 2018 +0100
@@ -623,8 +623,10 @@
testAllSplits(() -> new Decoder(256), hexdump, expectedHeaderTable, expectedHeaderList);
}
- private static void testAllSplits(Supplier<Decoder> supplier, String hexdump,
- String expectedHeaderTable, String expectedHeaderList) {
+ private static void testAllSplits(Supplier<Decoder> supplier,
+ String hexdump,
+ String expectedHeaderTable,
+ String expectedHeaderList) {
ByteBuffer source = SpecHelper.toBytes(hexdump);
BuffersTestingKit.forEachSplit(source, iterable -> {
@@ -651,6 +653,46 @@
assertEquals(d.getTable().getStateString(), expectedHeaderTable);
assertEquals(actual.stream().collect(Collectors.joining("\n")), expectedHeaderList);
});
+
+ // Now introduce last ByteBuffer which is empty and EOF (mimics idiom
+ // I've found in HttpClient code)
+ BuffersTestingKit.forEachSplit(source, iterable -> {
+ List<String> actual = new LinkedList<>();
+ Iterator<? extends ByteBuffer> i = iterable.iterator();
+ if (!i.hasNext()) {
+ return;
+ }
+ Decoder d = supplier.get();
+ do {
+ ByteBuffer n = i.next();
+ try {
+ d.decode(n, false, (name, value) -> {
+ if (value == null) {
+ actual.add(name.toString());
+ } else {
+ actual.add(name + ": " + value);
+ }
+ });
+ } catch (IOException e) {
+ throw new UncheckedIOException(e);
+ }
+ } while (i.hasNext());
+
+ try {
+ d.decode(ByteBuffer.allocate(0), false, (name, value) -> {
+ if (value == null) {
+ actual.add(name.toString());
+ } else {
+ actual.add(name + ": " + value);
+ }
+ });
+ } catch (IOException e) {
+ throw new UncheckedIOException(e);
+ }
+
+ assertEquals(d.getTable().getStateString(), expectedHeaderTable);
+ assertEquals(actual.stream().collect(Collectors.joining("\n")), expectedHeaderList);
+ });
}
//
--- a/test/jdk/java/net/httpclient/http2/java.net.http/jdk/internal/net/http/hpack/HuffmanTest.java Tue May 01 10:03:01 2018 +0100
+++ b/test/jdk/java/net/httpclient/http2/java.net.http/jdk/internal/net/http/hpack/HuffmanTest.java Tue May 01 19:14:46 2018 +0100
@@ -328,7 +328,7 @@
parseInt(hex, 16), parseInt(len));
StringBuilder actual = new StringBuilder();
- Huffman.Reader t = new Huffman.Reader();
+ NaiveHuffman.Reader t = new NaiveHuffman.Reader();
t.read(ByteBuffer.wrap(bytes), actual, false, true);
// What has been read MUST represent a single symbol
@@ -338,6 +338,8 @@
// characters (as some of them might not be visible)
assertEquals(actual.charAt(0), expected);
i++;
+
+ // maybe not report EOS but rather throw an expected exception?
}
assertEquals(i, 257); // 256 + EOS
}
@@ -503,12 +505,18 @@
}
@Test
+ public void read_13() {
+ read("6274 a6b4 0989 4de4 b27f 80",
+ "/https2/fixed?0");
+ }
+
+ @Test
public void test_trie_has_no_empty_nodes() {
- Huffman.Node root = Huffman.INSTANCE.getRoot();
- Stack<Huffman.Node> backlog = new Stack<>();
+ NaiveHuffman.Node root = NaiveHuffman.INSTANCE.getRoot();
+ Stack<NaiveHuffman.Node> backlog = new Stack<>();
backlog.push(root);
while (!backlog.isEmpty()) {
- Huffman.Node n = backlog.pop();
+ NaiveHuffman.Node n = backlog.pop();
// The only type of nodes we couldn't possibly catch during
// construction is an empty node: no children and no char
if (n.left != null) {
@@ -525,11 +533,11 @@
@Test
public void test_trie_has_257_nodes() {
int count = 0;
- Huffman.Node root = Huffman.INSTANCE.getRoot();
- Stack<Huffman.Node> backlog = new Stack<>();
+ NaiveHuffman.Node root = NaiveHuffman.INSTANCE.getRoot();
+ Stack<NaiveHuffman.Node> backlog = new Stack<>();
backlog.push(root);
while (!backlog.isEmpty()) {
- Huffman.Node n = backlog.pop();
+ NaiveHuffman.Node n = backlog.pop();
if (n.left != null) {
backlog.push(n.left);
}
@@ -546,7 +554,7 @@
@Test
public void cant_encode_outside_byte() {
TestHelper.Block<Object> coding =
- () -> new Huffman.Writer()
+ () -> new NaiveHuffman.Writer()
.from(((char) 256) + "", 0, 1)
.write(ByteBuffer.allocate(1));
RuntimeException e =
@@ -558,7 +566,7 @@
ByteBuffer source = SpecHelper.toBytes(hexdump);
Appendable actual = new StringBuilder();
try {
- new Huffman.Reader().read(source, actual, true);
+ new QuickHuffman.Reader().read(source, actual, true);
} catch (IOException e) {
throw new UncheckedIOException(e);
}
@@ -566,9 +574,9 @@
}
private static void write(String decoded, String hexdump) {
- int n = Huffman.INSTANCE.lengthOf(decoded);
+ Huffman.Writer writer = new QuickHuffman.Writer();
+ int n = writer.lengthOf(decoded);
ByteBuffer destination = ByteBuffer.allocate(n); // Extra margin (1) to test having more bytes in the destination than needed is ok
- Huffman.Writer writer = new Huffman.Writer();
BuffersTestingKit.forEachSplit(destination, byteBuffers -> {
writer.from(decoded, 0, decoded.length());
boolean written = false;