Convert groovy tests in javaagent and javaagent-bootstrap modules

javaagent-bootstrap/src/test/java/io/opentelemetry/javaagent/bootstrap/AgentClassLoaderTest.java

@@ -0,0 +1,108 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.javaagent.bootstrap;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import io.opentelemetry.sdk.OpenTelemetrySdk;
+import java.io.File;
+import java.lang.reflect.Method;
+import java.net.URL;
+import java.util.concurrent.Phaser;
+import org.junit.jupiter.api.Test;
+
+class AgentClassLoaderTest {
+
+  @Test
+  void agentClassloaderDoesNotLockClassloadingAroundInstance() throws Exception {
+    String className1 = "some/class/Name1";
+    String className2 = "some/class/Name2";
+    // any jar would do, use opentelemety sdk
+    URL testJarLocation =
+        OpenTelemetrySdk.class.getProtectionDomain().getCodeSource().getLocation();
+
+    try (AgentClassLoader loader = new AgentClassLoader(new File(testJarLocation.toURI()))) {
+      Phaser threadHoldLockPhase = new Phaser(2);
+      Phaser acquireLockFromMainThreadPhase = new Phaser(2);
+
+      // Use reflection to access protected getClassLoadingLock method
+      Method getClassLoadingLockMethod =
+          ClassLoader.class.getDeclaredMethod("getClassLoadingLock", String.class);
+      getClassLoadingLockMethod.setAccessible(true);
+
+      Thread thread1 =
+          new Thread(
+              () -> {
+                try {
+                  Object lock1 = getClassLoadingLockMethod.invoke(loader, className1);
+                  synchronized (lock1) {
+                    threadHoldLockPhase.arrive();
+                    acquireLockFromMainThreadPhase.arriveAndAwaitAdvance();
+                  }
+                } catch (Exception e) {
+                  throw new RuntimeException(e);
+                }
+              });
+      thread1.start();
+
+      Thread thread2 =
+          new Thread(
+              () -> {
+                try {
+                  threadHoldLockPhase.arriveAndAwaitAdvance();
+                  Object lock2 = getClassLoadingLockMethod.invoke(loader, className2);
+                  synchronized (lock2) {
+                    acquireLockFromMainThreadPhase.arrive();
+                  }
+                } catch (Exception e) {
+                  throw new RuntimeException(e);
+                }
+              });
+      thread2.start();
+
+      thread1.join();
+      thread2.join();
+      boolean applicationDidNotDeadlock = true;
+
+      assertThat(applicationDidNotDeadlock).isTrue();
+    }
+  }
+
+  @Test
+  void multiReleaseJar() throws Exception {
+    boolean jdk8 = "1.8".equals(System.getProperty("java.specification.version"));
+    Class<?> mrJarClass =
+        Class.forName("io.opentelemetry.instrumentation.resources.internal.ProcessArguments");
+    // sdk is a multi release jar
+    URL multiReleaseJar = mrJarClass.getProtectionDomain().getCodeSource().getLocation();
+
+    try (AgentClassLoader loader =
+        new AgentClassLoader(new File(multiReleaseJar.toURI())) {
+          @Override
+          protected String getClassSuffix() {
+            return "";
+          }
+        }) {
+      URL url =
+          loader.findResource(
+              "io/opentelemetry/instrumentation/resources/internal/ProcessArguments.class");
+
+      assertThat(url).isNotNull();
+      // versioned resource is found when not running on jdk 8
+      assertThat(url.toString().contains("META-INF/versions/9/")).isNotEqualTo(jdk8);
+
+      Class<?> clazz =
+          loader.loadClass("io.opentelemetry.instrumentation.resources.internal.ProcessArguments");
+      // class was loaded by agent loader used in this test
+      assertThat(clazz.getClassLoader()).isEqualTo(loader);
+      Method method = clazz.getDeclaredMethod("getProcessArguments");
+      method.setAccessible(true);
+      String[] result = (String[]) method.invoke(null);
+      // jdk8 versions returns empty array, jdk9 version does not
+      assertThat(result.length > 0).isNotEqualTo(jdk8);
+    }
+  }
+}