[#2187] Add CaffeineMessageAudit

Message audit using Caffeine cache with size-based TinyLfu eviction
paired with lock-free AtomicBitArrayBin for per-producer bit
operations. Provides bounded producer tracking with automatic
eviction, compared to ConcurrentMessageAudit
ConcurrentHashMap.

Author: mattrpav

activemq-client/pom.xml

@@ -66,6 +66,12 @@
       <scope>provided</scope>
     </dependency>
 
+    <dependency>
+      <groupId>com.github.ben-manes.caffeine</groupId>
+      <artifactId>caffeine</artifactId>
+      <version>3.2.4</version>
+    </dependency>
+
     <!-- =============================== -->
     <!-- Testing Dependencies -->
     <!-- =============================== -->

activemq-client/src/main/java/org/apache/activemq/CaffeineMessageAudit.java

@@ -0,0 +1,182 @@
+/**
+ * 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.activemq;
+
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+
+import org.apache.activemq.command.MessageId;
+import org.apache.activemq.command.ProducerId;
+import org.apache.activemq.util.AtomicBitArrayBin;
+import org.apache.activemq.util.IdGenerator;
+
+/**
+ * A message audit backed by Caffeine cache and {@link AtomicBitArrayBin}.
+ *
+ * <p>Uses Caffeine's {@link Cache} with size-based eviction (TinyLfu policy)
+ * for bounded producer tracking, paired with lock-free
+ * {@link AtomicBitArrayBin} for per-producer bit operations.
+ *
+ * <p>Producer count is bounded by {@link #getMaximumNumberOfProducersToTrack()}.
+ * Caffeine's TinyLfu admission policy evicts entries based on frequency and
+ * recency, providing near-optimal hit rates. The per-producer audit window is
+ * controlled by {@link #getAuditDepth()}.
+ *
+ * <p>All per-producer bit operations are lock-free via {@link AtomicBitArrayBin}.
+ * The only synchronization points are within Caffeine's internal structures
+ * for cache management.
+ */
+public class CaffeineMessageAudit {
+
+    public static final int DEFAULT_WINDOW_SIZE = 2048;
+    public static final int MAXIMUM_PRODUCER_COUNT = 64;
+
+    private volatile int auditDepth;
+    private volatile int maximumNumberOfProducersToTrack;
+    private volatile Cache<String, AtomicBitArrayBin> cache;
+
+    public CaffeineMessageAudit() {
+        this(DEFAULT_WINDOW_SIZE, MAXIMUM_PRODUCER_COUNT);
+    }
+
+    public CaffeineMessageAudit(int auditDepth, int maximumNumberOfProducersToTrack) {
+        this.auditDepth = auditDepth;
+        this.maximumNumberOfProducersToTrack = maximumNumberOfProducersToTrack;
+        this.cache = buildCache(maximumNumberOfProducersToTrack);
+    }
+
+    public int getAuditDepth() {
+        return auditDepth;
+    }
+
+    public void setAuditDepth(int auditDepth) {
+        this.auditDepth = auditDepth;
+    }
+
+    public int getMaximumNumberOfProducersToTrack() {
+        return maximumNumberOfProducersToTrack;
+    }
+
+    public void setMaximumNumberOfProducersToTrack(int maximumNumberOfProducersToTrack) {
+        this.maximumNumberOfProducersToTrack = maximumNumberOfProducersToTrack;
+        var newCache = buildCache(maximumNumberOfProducersToTrack);
+        newCache.putAll(this.cache.asMap());
+        this.cache = newCache;
+    }
+
+    public boolean isDuplicate(String id) {
+        var seed = IdGenerator.getSeedFromId(id);
+        if (seed == null) {
+            return false;
+        }
+        var bab = cache.get(seed, k -> new AtomicBitArrayBin(auditDepth));
+        var index = IdGenerator.getSequenceFromId(id);
+        if (index >= 0) {
+            return bab.setBit(index, true);
+        }
+        return false;
+    }
+
+    public boolean isDuplicate(final MessageId id) {
+        if (id == null) {
+            return false;
+        }
+        var pid = id.getProducerId();
+        if (pid == null) {
+            return false;
+        }
+        var bab = cache.get(pid.toString(), k -> new AtomicBitArrayBin(auditDepth));
+        return bab.setBit(id.getProducerSequenceId(), true);
+    }
+
+    public void rollback(final MessageId id) {
+        if (id == null) {
+            return;
+        }
+        var pid = id.getProducerId();
+        if (pid == null) {
+            return;
+        }
+        var bab = cache.getIfPresent(pid.toString());
+        if (bab != null) {
+            bab.setBit(id.getProducerSequenceId(), false);
+        }
+    }
+
+    public void rollback(final String id) {
+        var seed = IdGenerator.getSeedFromId(id);
+        if (seed == null) {
+            return;
+        }
+        var bab = cache.getIfPresent(seed);
+        if (bab != null) {
+            var index = IdGenerator.getSequenceFromId(id);
+            bab.setBit(index, false);
+        }
+    }
+
+    public boolean isInOrder(final String id) {
+        if (id == null) {
+            return true;
+        }
+        var seed = IdGenerator.getSeedFromId(id);
+        if (seed == null) {
+            return true;
+        }
+        var bab = cache.getIfPresent(seed);
+        if (bab != null) {
+            var index = IdGenerator.getSequenceFromId(id);
+            return bab.isInOrder(index);
+        }
+        return true;
+    }
+
+    public boolean isInOrder(final MessageId id) {
+        if (id == null) {
+            return false;
+        }
+        var pid = id.getProducerId();
+        if (pid == null) {
+            return false;
+        }
+        var bab = cache.get(pid.toString(), k -> new AtomicBitArrayBin(auditDepth));
+        return bab.isInOrder(id.getProducerSequenceId());
+    }
+
+    public long getLastSeqId(ProducerId id) {
+        var bab = cache.getIfPresent(id.toString());
+        if (bab != null) {
+            return bab.getLastSetIndex();
+        }
+        return -1;
+    }
+
+    public void clear() {
+        cache.invalidateAll();
+    }
+
+    public int getProducerCount() {
+        cache.cleanUp();
+        return (int) cache.estimatedSize();
+    }
+
+    private static Cache<String, AtomicBitArrayBin> buildCache(int maxSize) {
+        return Caffeine.newBuilder()
+                .maximumSize(maxSize)
+                .build();
+    }
+}