WebappClassLoader is parallel capable

- but it should be optimized.

Signed-off-by: David Matějček <david.matejcek@omnifish.ee>

appserver/web/war-util/pom.xml

@@ -101,5 +101,14 @@
             <artifactId>security-ee</artifactId>
             <version>${project.version}</version>
         </dependency>
+
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest</artifactId>
+        </dependency>
    </dependencies>
 </project>

appserver/web/war-util/src/main/java/org/glassfish/web/loader/WebappClassLoader.java

@@ -136,6 +136,10 @@
 public class WebappClassLoader extends GlassfishUrlClassLoader
     implements Reloader, InstrumentableClassLoader, PreDestroy, DDPermissionsLoader, JarFileResourcesProvider {
 
+    static {
+        registerAsParallelCapable();
+    }
+
     /** First try parent classloader, then own resources. */
     public static final boolean DELEGATE_DEFAULT = true;
     private static final Logger logger = LogFacade.getLogger();

appserver/web/war-util/src/test/java/org/glassfish/web/loader/WebappClassLoaderTest.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2023 Eclipse Foundation and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+
+package org.glassfish.web.loader;
+
+import java.net.URL;
+import java.net.URLClassLoader;
+
+import org.glassfish.common.util.GlassfishUrlClassLoader;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * @author David Matejcek
+ */
+public class WebappClassLoaderTest {
+
+    @Test
+    public void isParallel() {
+        assertAll(
+            () -> assertTrue(new URLClassLoader(new URL[0]).isRegisteredAsParallelCapable()),
+            () -> assertTrue(new GlassfishUrlClassLoader(new URL[0]).isRegisteredAsParallelCapable()),
+            () -> assertTrue(new WebappClassLoader().isRegisteredAsParallelCapable())
+        );
+    }
+}

nucleus/common/common-util/src/main/java/org/glassfish/common/util/GlassfishUrlClassLoader.java

@@ -34,6 +34,11 @@
  */
 public class GlassfishUrlClassLoader extends URLClassLoader {
 
+    static {
+        registerAsParallelCapable();
+    }
+
+
     /**
      * Initializes the internal classpath.
      *

nucleus/common/common-util/src/test/java/org/glassfish/common/util/GlassfishUrlClassLoaderTest.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2023 Eclipse Foundation and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+
+package org.glassfish.common.util;
+
+import java.net.URL;
+import java.net.URLClassLoader;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * @author David Matejcek
+ */
+public class GlassfishUrlClassLoaderTest {
+
+    @Test
+    public void isParallel() {
+        assertAll(
+            () -> assertTrue(new URLClassLoader(new URL[0]).isRegisteredAsParallelCapable()),
+            () -> assertTrue(new GlassfishUrlClassLoader(new URL[0]).isRegisteredAsParallelCapable())
+        );
+    }
+}