atomics: Java Atomics and VarHandle companion code

AtomicLong/LongAdder/VarHandle counters benchmarked against the synchronized and ReentrantLock baselines from the locks module, a deterministic ABA race against a hand-rolled Treiber stack plus the AtomicStampedReference fix, and a VarHandle access-modes demo (plain/opaque/acquire-release/volatile). Co-Authored-By: Claude Sonnet 5 <[email protected]> Claude-Session: https://claude.ai/code/session_01FhzLY5p6okFva3qsnsRyvM
2026-09-30 06:23:03 +00:00
parent 32b8067ecf
commit ff183da163
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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>com.ankurm</groupId>
+    <artifactId>java-core-examples</artifactId>
+    <version>1.0</version>
+  </parent>
+
+  <artifactId>atomics</artifactId>
+  <name>atomics</name>
+  <description>Java atomics and VarHandle: a counter written five ways, JMH throughput 1-64 threads, the ABA problem reproduced and fixed, and VarHandle's memory-ordering access modes.</description>
+
+  <properties>
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+      <version>${jmh.version}</version>
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+      <artifactId>jmh-generator-annprocess</artifactId>
+      <version>${jmh.version}</version>
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+      <artifactId>junit-jupiter</artifactId>
+      <version>5.11.0</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
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+        <groupId>org.apache.maven.plugins</groupId>
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+              <artifactId>jmh-generator-annprocess</artifactId>
+              <version>${jmh.version}</version>
+            </path>
+          </annotationProcessorPaths>
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+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
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+          </execution>
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+  </build>
+</project>