From e021f09f9fc12eedfb0a91ac516105ac4579e227 Mon Sep 17 00:00:00 2001
From: Gunther Rademacher <grd@gmx.net>
Date: Tue, 1 Sep 2026 11:21:24 +0200
Subject: [PATCH 1/2] add LRU cache for generated parsers

---
 .../basex/query/func/fn/FnInvisibleXml.java   | 42 ++++++++++++++++++-
 1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java b/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
index 06f0e79a00..af3b0476d4 100644
--- a/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
+++ b/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
@@ -3,6 +3,7 @@
 import static org.basex.query.QueryError.*;
 
 import java.io.*;
+import java.util.*;
 
 import org.basex.build.*;
 import org.basex.core.*;
@@ -74,6 +75,17 @@ private final class Generator {
     private static final Option[] NO_OPTS = new Blitz.Option[0];
     /** Markup Blitz options for fail-on-error. */
     private static final Option[] FAIL_OPTS = new Blitz.Option[] { Blitz.Option.FAIL_ON_ERROR };
+    /** Maximum number of entries. */
+    private static final int MAX = 15;
+    /** Generated parser cache. */
+    private static final LinkedHashMap<String, de.bottlecaps.markup.blitz.Parser> PARSERS =
+        new LinkedHashMap<>(MAX + 1, 1.0f, true) {
+          @Override
+          protected boolean removeEldestEntry(
+              final Map.Entry<String, de.bottlecaps.markup.blitz.Parser> eldest) {
+            return size() > MAX;
+          }
+        };
 
     /**
      * Generate a parser from an invisible XML grammar.
@@ -97,7 +109,7 @@ public FuncItem generate(final QueryContext qc) throws QueryException {
       final de.bottlecaps.markup.blitz.Parser parser;
       final Blitz.Option[] opts = options.get(IxmlOptions.FAIL_ON_ERROR) ? FAIL_OPTS : NO_OPTS;
       try {
-        parser = xml ? Blitz.generateFromXml(grmmr, opts) : Blitz.generate(grmmr, opts);
+        parser = parser(grmmr, xml, opts);
       } catch(final BlitzParseException ex) {
         throw IXML_GRM_X_X_X.get(info, ex.getOffendingToken(), ex.getLine(), ex.getColumn());
       } catch(final BlitzException ex) {
@@ -110,6 +122,34 @@ public FuncItem generate(final QueryContext qc) throws QueryException {
       final FuncType ft = FuncType.get(parseFunction.seqType(), Types.STRING_O);
       return new FuncItem(info, parseFunction, params, AnnList.EMPTY, ft, params.length, null);
     }
+
+    /**
+     * Returns a cached parser.
+     * @param grammar grammar string
+     * @param xml XML grammar flag
+     * @param opts generation options
+     * @return parser
+     */
+    private de.bottlecaps.markup.blitz.Parser parser(final String grammar, final boolean xml,
+        final Blitz.Option[] opts) {
+      final String key = grammar + "\0" + xml + "\0" + Arrays.toString(opts);
+      de.bottlecaps.markup.blitz.Parser parser;
+      synchronized(PARSERS) {
+        parser = PARSERS.get(key);
+      }
+      if(parser == null) {
+        parser = xml ? Blitz.generateFromXml(grammar, opts) : Blitz.generate(grammar, opts);
+        synchronized(PARSERS) {
+          final de.bottlecaps.markup.blitz.Parser cached = PARSERS.get(key);
+          if(cached != null) {
+            parser = cached;
+          } else {
+            PARSERS.put(key, parser);
+          }
+        }
+      }
+      return parser;
+    }
   }
 
   /**

From b2d4eba30ac3deb957fc2a0c44470ff0687fc9c9 Mon Sep 17 00:00:00 2001
From: Gunther Rademacher <grd@gmx.net>
Date: Tue, 1 Sep 2026 11:43:36 +0200
Subject: [PATCH 2/2] minor changes

---
 .../main/java/org/basex/query/func/fn/FnInvisibleXml.java | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java b/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
index af3b0476d4..04fc7940dc 100644
--- a/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
+++ b/basex-core/src/main/java/org/basex/query/func/fn/FnInvisibleXml.java
@@ -75,15 +75,15 @@ private final class Generator {
     private static final Option[] NO_OPTS = new Blitz.Option[0];
     /** Markup Blitz options for fail-on-error. */
     private static final Option[] FAIL_OPTS = new Blitz.Option[] { Blitz.Option.FAIL_ON_ERROR };
-    /** Maximum number of entries. */
-    private static final int MAX = 15;
+    /** Maximum number of parser cache entries. */
+    private static final int CACHE_SIZE = 15;
     /** Generated parser cache. */
     private static final LinkedHashMap<String, de.bottlecaps.markup.blitz.Parser> PARSERS =
-        new LinkedHashMap<>(MAX + 1, 1.0f, true) {
+        new LinkedHashMap<>(CACHE_SIZE + 1, 1.0f, true) {
           @Override
           protected boolean removeEldestEntry(
               final Map.Entry<String, de.bottlecaps.markup.blitz.Parser> eldest) {
-            return size() > MAX;
+            return size() > CACHE_SIZE;
           }
         };