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Posted to commits@tika.apache.org by ta...@apache.org on 2026/09/02 20:07:35 UTC
(tika) 11/13: TIKA-4868: incremental HTML probe stripping; BMP table for block lookup
This is an automated email from the ASF dual-hosted git repository.
tballison pushed a commit to branch TIKA-4868-performance-improvements
in repository https://gitbox.apache.org/repos/asf/tika.git
commit 39d5e7f44384d69501b5f8481fcbc5266102b81c
Author: tallison <ta...@apache.org>
AuthorDate: Wed Sep 2 08:41:36 2026 -0400
TIKA-4868: incremental HTML probe stripping; BMP table for block lookup
---
CHANGES.txt | 10 ++
.../apache/tika/ml/chardetect/AdaptiveProbe.java | 12 ++-
.../tika/ml/chardetect/HtmlByteStripper.java | 115 ++++++++++++++++----
.../ml/chardetect/HtmlByteStripperResumeTest.java | 117 +++++++++++++++++++++
.../tika/ml/junkdetect/UnicodeBlockRanges.java | 20 ++++
.../tika/ml/junkdetect/UnicodeBlockRangesTest.java | 14 +++
6 files changed, 263 insertions(+), 25 deletions(-)
diff --git a/CHANGES.txt b/CHANGES.txt
index c2b46bd0ac..f125119319 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,5 +1,15 @@
Release 4.1.0 - unreleased
+ * Mojibuster's adaptive probe strips incrementally instead of
+ re-stripping the whole buffer on every read (quadratic in read count
+ on tag-heavy pages; a 293KB page's probe drops 4.5ms -> 0.8ms).
+ Byte-identical: the resumable scanner holds back at a chunk-final
+ "<!" so chunked == single-shot at every boundary (exhaustive
+ boundary tests), and detection output was unchanged across a
+ 3,034-file differential. JunkDetector's Unicode block lookup also
+ uses a precomputed BMP table (exhaustive equivalence test)
+ (TIKA-4868).
+
* Markdown rendering is another ~8x faster on large documents:
a custom Text-node renderer emits unescaped spans in bulk instead of
commonmark's per-character escape-check-and-append (9MB render
diff --git a/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/AdaptiveProbe.java b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/AdaptiveProbe.java
index e2100b0533..f9aa049890 100644
--- a/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/AdaptiveProbe.java
+++ b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/AdaptiveProbe.java
@@ -61,6 +61,10 @@ public final class AdaptiveProbe {
int cap = Math.min(rawCap, contentTarget);
byte[] buf = new byte[cap];
byte[] stripDst = new byte[cap];
+ // Resumable strip: each byte is scanned once. Re-stripping from offset 0
+ // per read made this loop quadratic in read count on tag-heavy pages.
+ // Absolute cursor positions stay valid across the copyOf growth below.
+ HtmlByteStripper.Cursor cursor = new HtmlByteStripper.Cursor();
int total = 0;
while (total < rawCap) {
int want = Math.min(rawCap - total, contentTarget);
@@ -71,10 +75,10 @@ public final class AdaptiveProbe {
}
int n = IOUtils.read(tis, buf, total, want);
total += n;
- HtmlByteStripper.Result r =
- HtmlByteStripper.stripTags(buf, 0, total, stripDst, 0);
- int content = r.tagCount > 0 ? r.length : total;
- if (content >= contentTarget || n < want) {
+ boolean eof = n < want;
+ HtmlByteStripper.stripTags(buf, total, stripDst, cursor, eof);
+ int content = cursor.tagCount() > 0 ? cursor.contentLength() : total;
+ if (content >= contentTarget || eof) {
break; // enough body text, or EOF
}
}
diff --git a/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/HtmlByteStripper.java b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/HtmlByteStripper.java
index 37ae5ad26b..9b2aa44937 100644
--- a/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/HtmlByteStripper.java
+++ b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/main/java/org/apache/tika/ml/chardetect/HtmlByteStripper.java
@@ -184,27 +184,93 @@ public final class HtmlByteStripper {
return strip(src, srcOffset, srcLen, dst, dstOffset, false);
}
+ /**
+ * Scan state carried across chunked {@link #stripTags(byte[], int, byte[], Cursor,
+ * boolean)} calls. All positions are absolute indices into the caller's (growing)
+ * source buffer, so the buffer must retain its prefix across calls (e.g. grow with
+ * {@code Arrays.copyOf}). Tags-only: the resumable path never drops entities.
+ */
+ static final class Cursor {
+ private int state = TEXT;
+ private int nameStart;
+ private byte[] rawEnd;
+ private int rawMatch;
+ private int tagCount;
+ private int entityCount;
+ private int entityStart;
+ private int attrNameStart;
+ private boolean emitAttrValue;
+ private int written;
+ private int next;
+ // where the very first scan started; guards the comment lookbehind
+ private int origin;
+
+ int contentLength() {
+ return written;
+ }
+
+ int tagCount() {
+ return tagCount;
+ }
+ }
+
+ /**
+ * Resumable {@link #stripTags(byte[], int, int, byte[], int)}: scans
+ * {@code src[cursor.next .. end)}, appending stripped output at
+ * {@code dst[cursor.written]}. Byte-identical to a single-shot strip of the final
+ * buffer: on a non-final call the scan holds back at a {@code <!} too close to
+ * {@code end} for the comment lookahead, so the next call re-examines it with more
+ * bytes; everything else in the machine is strictly left-to-right.
+ *
+ * @param isFinal true on the last call (no more input will arrive)
+ */
+ static void stripTags(byte[] src, int end, byte[] dst, Cursor cursor, boolean isFinal) {
+ scan(src, end, dst, cursor, false, isFinal);
+ }
+
private static Result strip(byte[] src, int srcOffset, int srcLen,
byte[] dst, int dstOffset, boolean dropEntities) {
- int w = dstOffset;
- int state = TEXT;
- int nameStart = 0;
- byte[] rawEnd = null;
- int rawMatch = 0;
+ Cursor c = new Cursor();
+ c.next = srcOffset;
+ c.origin = srcOffset;
+ c.written = dstOffset;
int end = srcOffset + srcLen;
- int tagCount = 0;
- int entityCount = 0;
+ scan(src, end, dst, c, dropEntities, true);
+ int w = c.written;
+
+ // Unterminated entity at EOF: emit consumed prefix as literal text.
+ if (c.state == ENTITY || c.state == ENTITY_NAME || c.state == ENTITY_NUM
+ || c.state == ENTITY_DEC || c.state == ENTITY_HEX) {
+ for (int k = c.entityStart; k < end; k++) {
+ dst[w++] = src[k];
+ }
+ }
+
+ return new Result(w - dstOffset, c.tagCount, c.entityCount);
+ }
+
+ private static void scan(byte[] src, int end, byte[] dst, Cursor c,
+ boolean dropEntities, boolean isFinal) {
+ int w = c.written;
+ int state = c.state;
+ int nameStart = c.nameStart;
+ byte[] rawEnd = c.rawEnd;
+ int rawMatch = c.rawMatch;
+ int tagCount = c.tagCount;
+ int entityCount = c.entityCount;
// Position of the leading '&' for the in-progress entity.
// Tracked so the bailout path can emit the consumed prefix
// as literal text when the parse fails (e.g. "AT&T").
- int entityStart = 0;
- int attrNameStart = 0;
+ int entityStart = c.entityStart;
+ int attrNameStart = c.attrNameStart;
// When true, the current quoted attribute value's bytes are
// emitted to dst (attribute name matched TEXT_ATTRS). Reset
// to false when the quote closes or the tag ends.
- boolean emitAttrValue = false;
+ boolean emitAttrValue = c.emitAttrValue;
- for (int i = srcOffset; i < end; i++) {
+ int i = c.next;
+ outer:
+ for (; i < end; i++) {
byte b = src[i];
switch (state) {
case TEXT:
@@ -219,6 +285,11 @@ public final class HtmlByteStripper {
break;
case LT:
+ if (b == '!' && i + 2 >= end && !isFinal) {
+ // comment lookahead needs 2 more bytes: hold back so the next
+ // call re-examines '!' -- keeps chunked == single-shot
+ break outer;
+ }
if (b == '!' && i + 2 < end
&& src[i + 1] == '-' && src[i + 2] == '-') {
state = COMMENT;
@@ -474,7 +545,7 @@ public final class HtmlByteStripper {
break;
case COMMENT:
- if (b == '>' && i >= srcOffset + 2
+ if (b == '>' && i >= c.origin + 2
&& src[i - 1] == '-' && src[i - 2] == '-') {
state = TEXT;
}
@@ -508,15 +579,17 @@ public final class HtmlByteStripper {
}
}
- // Unterminated entity at EOF: emit consumed prefix as literal text.
- if (state == ENTITY || state == ENTITY_NAME || state == ENTITY_NUM
- || state == ENTITY_DEC || state == ENTITY_HEX) {
- for (int k = entityStart; k < end; k++) {
- dst[w++] = src[k];
- }
- }
-
- return new Result(w - dstOffset, tagCount, entityCount);
+ c.state = state;
+ c.nameStart = nameStart;
+ c.rawEnd = rawEnd;
+ c.rawMatch = rawMatch;
+ c.tagCount = tagCount;
+ c.entityCount = entityCount;
+ c.entityStart = entityStart;
+ c.attrNameStart = attrNameStart;
+ c.emitAttrValue = emitAttrValue;
+ c.written = w;
+ c.next = i;
}
/**
diff --git a/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/test/java/org/apache/tika/ml/chardetect/HtmlByteStripperResumeTest.java b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/test/java/org/apache/tika/ml/chardetect/HtmlByteStripperResumeTest.java
new file mode 100644
index 0000000000..77a2508a21
--- /dev/null
+++ b/tika-encoding-detectors/tika-encoding-detector-mojibuster/src/test/java/org/apache/tika/ml/chardetect/HtmlByteStripperResumeTest.java
@@ -0,0 +1,117 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.tika.ml.chardetect;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.Random;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Chunked stripTags with a carried Cursor must be byte-identical to the single-shot
+ * strip of the final buffer, for every chunking -- including boundaries inside tags,
+ * comments (the {@code <!} lookahead hold-back), raw script/style bodies, quoted
+ * attribute values, and multibyte UTF-8 sequences.
+ */
+public class HtmlByteStripperResumeTest {
+
+ private static final String[] SAMPLES = {
+ "plain text, no markup at all — even multibyte: čšž 中文 🚀",
+ "<html><head><title>t</title></head><body>Hello <b>world</b></body></html>",
+ "before<!-- a comment with <tags> inside -->after",
+ "x<!-- unterminated comment...",
+ "a<!DOCTYPE html>b<?xml version=\"1.0\"?>c",
+ "<script>var a = '<div>'; // not a tag </script>text<style>.x{}</style>tail",
+ "<img alt=\"seen text\" src=\"nope.png\" title='also seen'>body",
+ "AT&T & friends A B ¬anentity; &unterminated",
+ "stray < less-than and << double and <3 hearts",
+ "<a href=\"x\">link</a><ul><li>item</li></ul>",
+ "<div class='q' aria-label=\"read me\">deep</div>",
+ "čšž<em>中文</em>🚀<!--中-->done",
+ "text</scripted>more<script>raw</script>end",
+ "<!",
+ "<!-",
+ "<!--",
+ "<!-->",
+ "<!---->tail",
+ };
+
+ @Test
+ public void testEveryBoundaryEqualsSingleShot() {
+ for (String sample : SAMPLES) {
+ byte[] src = sample.getBytes(StandardCharsets.UTF_8);
+ Expected want = singleShot(src);
+ // every single split point, and every pair of split points
+ for (int cut = 0; cut <= src.length; cut++) {
+ check(src, new int[]{cut}, want, sample);
+ }
+ for (int c1 = 0; c1 <= src.length; c1 += 3) {
+ for (int c2 = c1; c2 <= src.length; c2 += 3) {
+ check(src, new int[]{c1, c2}, want, sample);
+ }
+ }
+ }
+ }
+
+ @Test
+ public void testRandomChunkingsOnConcatenatedSamples() {
+ StringBuilder sb = new StringBuilder();
+ for (int i = 0; i < 50; i++) {
+ sb.append(SAMPLES[i % SAMPLES.length]);
+ }
+ byte[] src = sb.toString().getBytes(StandardCharsets.UTF_8);
+ Expected want = singleShot(src);
+ Random random = new Random(42);
+ for (int trial = 0; trial < 200; trial++) {
+ int nCuts = 1 + random.nextInt(8);
+ int[] cuts = new int[nCuts];
+ for (int i = 0; i < nCuts; i++) {
+ cuts[i] = random.nextInt(src.length + 1);
+ }
+ Arrays.sort(cuts);
+ check(src, cuts, want, "concat trial " + trial);
+ }
+ }
+
+ private record Expected(byte[] out, int tagCount) {
+ }
+
+ private static Expected singleShot(byte[] src) {
+ byte[] dst = new byte[src.length + 16];
+ HtmlByteStripper.Result r = HtmlByteStripper.stripTags(src, 0, src.length, dst, 0);
+ return new Expected(Arrays.copyOf(dst, r.length), r.tagCount);
+ }
+
+ private static void check(byte[] src, int[] cuts, Expected want, String label) {
+ byte[] dst = new byte[src.length + 16];
+ HtmlByteStripper.Cursor cursor = new HtmlByteStripper.Cursor();
+ int prev = 0;
+ for (int cut : cuts) {
+ int end = Math.max(prev, cut);
+ HtmlByteStripper.stripTags(src, end, dst, cursor, false);
+ prev = end;
+ }
+ HtmlByteStripper.stripTags(src, src.length, dst, cursor, true);
+ assertEquals(want.tagCount(), cursor.tagCount(), label + " cuts=" + Arrays.toString(cuts));
+ assertArrayEquals(want.out(), Arrays.copyOf(dst, cursor.contentLength()),
+ label + " cuts=" + Arrays.toString(cuts));
+ }
+}
diff --git a/tika-ml/tika-ml-junkdetect/src/main/java/org/apache/tika/ml/junkdetect/UnicodeBlockRanges.java b/tika-ml/tika-ml-junkdetect/src/main/java/org/apache/tika/ml/junkdetect/UnicodeBlockRanges.java
index ab7e1b00b7..6eb0dc32c3 100644
--- a/tika-ml/tika-ml-junkdetect/src/main/java/org/apache/tika/ml/junkdetect/UnicodeBlockRanges.java
+++ b/tika-ml/tika-ml-junkdetect/src/main/java/org/apache/tika/ml/junkdetect/UnicodeBlockRanges.java
@@ -399,11 +399,24 @@ public final class UnicodeBlockRanges {
/** Cached start_cp array for binary search. */
private static final int[] STARTS;
+
+ /**
+ * Precomputed bucket per BMP codepoint (128KB): bucketOf runs per character of
+ * every scored text, and the binary search was a visible share of junk-detection
+ * time. Filled from {@link #searchBucketOf(int)}, so the answers are identical
+ * by construction; supplementary planes stay on the search path.
+ */
+ private static final short[] BMP_BUCKETS;
+
static {
STARTS = new int[RANGES.length];
for (int i = 0; i < RANGES.length; i++) {
STARTS[i] = RANGES[i][0];
}
+ BMP_BUCKETS = new short[0x10000];
+ for (int cp = 0; cp < 0x10000; cp++) {
+ BMP_BUCKETS[cp] = (short) searchBucketOf(cp);
+ }
}
private UnicodeBlockRanges() {
@@ -423,6 +436,13 @@ public final class UnicodeBlockRanges {
* O(log N) where N = {@value #UNASSIGNED} (the number of named blocks).
*/
public static int bucketOf(int cp) {
+ if (cp >= 0 && cp < 0x10000) {
+ return BMP_BUCKETS[cp];
+ }
+ return searchBucketOf(cp);
+ }
+
+ private static int searchBucketOf(int cp) {
// Binary search: find largest STARTS[i] <= cp
int lo = 0;
int hi = STARTS.length - 1;
diff --git a/tika-ml/tika-ml-junkdetect/src/test/java/org/apache/tika/ml/junkdetect/UnicodeBlockRangesTest.java b/tika-ml/tika-ml-junkdetect/src/test/java/org/apache/tika/ml/junkdetect/UnicodeBlockRangesTest.java
index e25cff9204..22576a1a77 100644
--- a/tika-ml/tika-ml-junkdetect/src/test/java/org/apache/tika/ml/junkdetect/UnicodeBlockRangesTest.java
+++ b/tika-ml/tika-ml-junkdetect/src/test/java/org/apache/tika/ml/junkdetect/UnicodeBlockRangesTest.java
@@ -111,4 +111,18 @@ public class UnicodeBlockRangesTest {
assertTrue(seen[b], "Bucket id " + b + " is never produced by any codepoint");
}
}
+
+ @org.junit.jupiter.api.Test
+ public void testBmpTableMatchesSearchEverywhere() throws Exception {
+ // the BMP fast table must agree with the binary search for every codepoint,
+ // including plane boundaries and a sweep of the supplementary planes
+ java.lang.reflect.Method search =
+ UnicodeBlockRanges.class.getDeclaredMethod("searchBucketOf", int.class);
+ search.setAccessible(true);
+ for (int cp = 0; cp <= 0x10FFFF; cp += (cp < 0x10000 ? 1 : 17)) {
+ org.junit.jupiter.api.Assertions.assertEquals(
+ (int) (Integer) search.invoke(null, cp),
+ UnicodeBlockRanges.bucketOf(cp), "cp=" + Integer.toHexString(cp));
+ }
+ }
}