synchronizers: CountDownLatch vs CyclicBarrier vs Phaser vs Semaphore

One three-round worker pipeline implemented with CountDownLatch (one latch per round), CyclicBarrier (reusable, with a barrier action), and Phaser (reusable, plus dynamic mid-run registration), alongside Semaphore solving the genuinely different problem of bounding concurrent access. Covers timeout behavior (CyclicBarrier permanently breaks on one timeout, Phaser doesn't) and virtual-thread compatibility, including the corrected finding that Object.wait() releases its monitor and never pinned, unlike Thread.sleep() inside synchronized. Co-Authored-By: Claude Sonnet 5 <[email protected]> Claude-Session: https://claude.ai/code/session_01FhzLY5p6okFva3qsnsRyvM
2026-09-30 06:43:52 +00:00
parent 0819993c51
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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>synchronizers</artifactId>
+  <name>synchronizers</name>
+  <description>CountDownLatch vs CyclicBarrier vs Phaser vs Semaphore: one three-round worker pipeline implemented four ways, reuse semantics, timeout behavior, and virtual-thread compatibility.</description>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
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+      <version>5.11.0</version>
+      <scope>test</scope>
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+  <build>
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+        <configuration>
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+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
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+  </build>
+</project>