Consolidate Java 21 specific tests in a separate Maven module.

Motivation:

Java 21 specific tests are still remaining in vertx-core tests using reflection and assume statements.

We should group all of that in a java 21 Maven module that run those tests.

Changes:

Rename vertx-core-jackson-v3 to vertx-core-java21-tests.

Move Java 21 tests there.

Author: vietj

pom.xml

@@ -81,7 +81,7 @@
       <modules>
         <module>vertx-core-logging</module>
         <module>vertx-core</module>
-        <module>vertx-core-jackson-v3</module>
+        <module>vertx-core-java21-tests</module>
       </modules>
     </profile>
 

vertx-core-jackson-v3/src/test/java/module-info.java

@@ -20,7 +20,7 @@
     <version>5.1.0-SNAPSHOT</version>
   </parent>
 
-  <artifactId>vertx-core-jackson-v3</artifactId>
+  <artifactId>vertx-core-java21-it</artifactId>
   <version>5.1.0-SNAPSHOT</version>
 
   <name>Vert.x Core Jackson v3 plugin</name>
@@ -83,16 +83,46 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-surefire-plugin</artifactId>
-        <version>3.5.3</version>
-        <configuration>
-          <excludes>
-            <exclude>io/vertx/it/**</exclude>
-          </excludes>
-          <classpathDependencyExcludes>
-            <classpathDependencyExclude>com.fasterxml.jackson.core:jackson-core</classpathDependencyExclude>
-            <classpathDependencyExclude>com.fasterxml.jackson.core:jackson-databind</classpathDependencyExclude>
-          </classpathDependencyExcludes>
-        </configuration>
+        <executions>
+          <execution>
+            <id>default-test</id>
+            <configuration>
+              <includes>
+                <include>io/vertx/tests/virtualthread/**</include>
+              </includes>
+            </configuration>
+          </execution>
+          <execution>
+            <id>jacksonv2-test</id>
+            <configuration>
+              <classpathDependencyExcludes>
+                <classpathDependencyExclude>tools.jackson.core:jackson-core</classpathDependencyExclude>
+                <classpathDependencyExclude>tools.jackson.core:jackson-databind</classpathDependencyExclude>
+              </classpathDependencyExcludes>
+              <includes>
+                <include>io/vertx/tests/jacksonv2/**</include>
+              </includes>
+            </configuration>
+            <goals>
+              <goal>test</goal>
+            </goals>
+          </execution>
+          <execution>
+            <id>jacksonv3-test</id>
+            <configuration>
+              <classpathDependencyExcludes>
+                <classpathDependencyExclude>com.fasterxml.jackson.core:jackson-core</classpathDependencyExclude>
+                <classpathDependencyExclude>com.fasterxml.jackson.core:jackson-databind</classpathDependencyExclude>
+              </classpathDependencyExcludes>
+              <includes>
+                <include>io/vertx/tests/jacksonv3/**</include>
+              </includes>
+            </configuration>
+            <goals>
+              <goal>test</goal>
+            </goals>
+          </execution>
+        </executions>
       </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>

vertx-core-jackson-v3/pom.xml vertx-core-java21-tests/pom.xmlvertx-core-jackson-v3/pom.xml renamed to vertx-core-java21-tests/pom.xml

@@ -0,0 +1,55 @@
+package io.vertx.tests.jacksonv2;
+
+import com.fasterxml.jackson.core.util.BufferRecycler;
+import io.vertx.core.json.jackson.HybridJacksonPool;
+import org.junit.Assume;
+import org.junit.Test;
+
+import java.util.concurrent.CountDownLatch;
+
+import static org.junit.Assert.*;
+
+public class HybridJacksonPoolTest {
+
+  @Test
+  public void testVirtualThreadPoolWithMultipleThreads() {
+    int stripesCount = 4;
+    HybridJacksonPool.StripedLockFreePool virtualPool = new HybridJacksonPool.StripedLockFreePool(stripesCount);
+    int nThreads = 100;
+    BufferRecycler[] resources = new BufferRecycler[nThreads];
+    CountDownLatch latch = new CountDownLatch(nThreads);
+
+    for (int i = 0; i < nThreads; i++) {
+      int threadIndex = i;
+      Thread.startVirtualThread(() -> {
+        resources[threadIndex] = virtualPool.acquirePooled();
+        latch.countDown();
+      });
+    }
+
+    try {
+      latch.await();
+    } catch (InterruptedException e) {
+      throw new RuntimeException(e);
+    }
+    assertEquals(0, virtualPool.size());
+
+    for (int i = 0; i < nThreads; i++) {
+      virtualPool.releasePooled(resources[i]);
+    }
+
+    // check that all resources have been released back to the pool
+    assertEquals(nThreads, virtualPool.size());
+
+    int avgResourcesNrPerStripe = nThreads / stripesCount;
+    int minResourcesNrPerStripe = avgResourcesNrPerStripe / 2;
+    int maxResourcesNrPerStripe = avgResourcesNrPerStripe * 2;
+
+    // check that all the stripes in the pool are reasonably balanced
+    int[] poolStats = virtualPool.stackStats();
+    for (int i = 0; i < stripesCount; i++) {
+      assertTrue(poolStats[i] >= minResourcesNrPerStripe);
+      assertTrue(poolStats[i] <= maxResourcesNrPerStripe);
+    }
+  }
+}