merge #231 - [ARTEMIS-294] Use doPriviledged block for ServiceLoader

artemis-service-extensions/src/main/java/org/apache/activemq/artemis/service/extensions/ServiceUtils.java

@@ -16,12 +16,15 @@
  */
 package org.apache.activemq.artemis.service.extensions;
 
-import javax.transaction.TransactionManager;
+import java.security.AccessController;
-import javax.transaction.xa.XAResource;
+import java.security.PrivilegedAction;
 import java.util.Iterator;
 import java.util.Map;
 import java.util.ServiceLoader;
 
+import javax.transaction.TransactionManager;
+import javax.transaction.xa.XAResource;
+
 import org.apache.activemq.artemis.service.extensions.transactions.TransactionManagerLocator;
 import org.apache.activemq.artemis.service.extensions.xa.ActiveMQXAResourceWrapper;
 import org.apache.activemq.artemis.service.extensions.xa.ActiveMQXAResourceWrapperFactory;
@@ -37,7 +40,7 @@ public class ServiceUtils {
 
    private static ActiveMQXAResourceWrapperFactory getActiveMQXAResourceWrapperFactory() {
       if (activeMQXAResourceWrapperFactory == null) {
-         setActiveMQXAResourceWrapperFactory(ServiceLoader.load(ActiveMQXAResourceWrapperFactory.class));
+         activeMQXAResourceWrapperFactory = findActiveMQXAResourceWrapperFactory();
       }
       return activeMQXAResourceWrapperFactory;
    }
@@ -48,11 +51,7 @@ public class ServiceUtils {
 
    public static synchronized TransactionManager getTransactionManager() {
       if (!transactionManagerLoaded) {
-         Iterator<TransactionManagerLocator> it = ServiceLoader.load(TransactionManagerLocator.class).iterator();
+         transactionManager = findTransactionManager();
-         while (it.hasNext() && transactionManager == null) {
-            transactionManager = it.next().getTransactionManager();
-         }
-
          if (transactionManager != null) {
             transactionManagerLoaded = true;
          }
@@ -68,13 +67,39 @@ public class ServiceUtils {
       transactionManagerLoaded = (transactionManager != null);
    }
 
-   private static void setActiveMQXAResourceWrapperFactory(Iterable<ActiveMQXAResourceWrapperFactory> iterable) {
+
-      if (iterable.iterator().hasNext()) {
+   /**
-         activeMQXAResourceWrapperFactory = iterable.iterator().next();
+    *  Find the <em>first</em> transaction manager loaded from the {@code TransactionManagerLocator} service or {@code null} if none is loaded.
-      }
+    */
-      else {
+   private static TransactionManager findTransactionManager() {
-         activeMQXAResourceWrapperFactory = new ActiveMQXAResourceWrapperFactoryImpl();
+      return AccessController.doPrivileged(new PrivilegedAction<TransactionManager>() {
-      }
+         @Override
+         public TransactionManager run() {
+            Iterator<TransactionManagerLocator> it = ServiceLoader.load(TransactionManagerLocator.class, ServiceUtils.class.getClassLoader()).iterator();
+            while (it.hasNext() && transactionManager == null) {
+               transactionManager = it.next().getTransactionManager();
+            }
+            return transactionManager;
+         }
+      });
    }
 
+   /**
+    *  Find the <em>first</em> wrapper factory loaded from the {@code ActiveMQXAResourceWrapperFactory} service or
+    *  use the default {@code ActiveMQXAResourceWrapperFactoryImpl} if none is loaded.
+    */
+   private static ActiveMQXAResourceWrapperFactory findActiveMQXAResourceWrapperFactory() {
+      return AccessController.doPrivileged(new PrivilegedAction<ActiveMQXAResourceWrapperFactory>() {
+         @Override
+         public ActiveMQXAResourceWrapperFactory run() {
+            Iterator<ActiveMQXAResourceWrapperFactory> iterator = ServiceLoader.load(ActiveMQXAResourceWrapperFactory.class, ServiceUtils.class.getClassLoader()).iterator();
+            if (iterator.hasNext()) {
+               return iterator.next();
+            }
+            else {
+               return new ActiveMQXAResourceWrapperFactoryImpl();
+            }
+         }
+      });
+   }
 }

artemis-service-extensions/src/test/java/org/apache/activemq/artemis/service/extensions/tests/xa/ServiceUtilsTest.java

@@ -16,44 +16,20 @@
  */
 package org.apache.activemq.artemis.service.extensions.tests.xa;
 
-import java.lang.reflect.Field;
+import static org.jgroups.util.Util.assertTrue;
+
 import java.lang.reflect.Method;
-import java.util.ArrayList;
-import java.util.List;
 
 import org.apache.activemq.artemis.service.extensions.ServiceUtils;
-import org.apache.activemq.artemis.service.extensions.xa.ActiveMQXAResourceWrapperFactory;
-import org.apache.activemq.artemis.service.extensions.xa.ActiveMQXAResourceWrapperFactoryImpl;
 import org.junit.Test;
 
-import static org.jgroups.util.Util.assertTrue;
-
 public class ServiceUtilsTest {
 
    @Test
-   public void testSetActiveMQXAResourceWrapperFactorySetsDefaultImplWhenNoOther() throws Exception {
+   public void testGetActiveMQXAResourceWrapperFactoryLoadsService() throws Exception {
-      List<ActiveMQXAResourceWrapperFactory> factories = new ArrayList<ActiveMQXAResourceWrapperFactory>();
+      Method method = ServiceUtils.class.getDeclaredMethod("getActiveMQXAResourceWrapperFactory");
-
-      Method method = ServiceUtils.class.getDeclaredMethod("setActiveMQXAResourceWrapperFactory", Iterable.class);
       method.setAccessible(true);
-      method.invoke(null, factories);
+      Object o = method.invoke(null);
-
+      assertTrue(o instanceof MockActiveMQResourceWrapperFactory);
-      Field field = ServiceUtils.class.getDeclaredField("activeMQXAResourceWrapperFactory");
-      field.setAccessible(true);
-      assertTrue(field.get(null) instanceof ActiveMQXAResourceWrapperFactoryImpl);
-   }
-
-   @Test
-   public void testSetActiveMQXAResourceWrapperFactorySetsExtensionImplWhenSupplied() throws Exception {
-      List<ActiveMQXAResourceWrapperFactory> factories = new ArrayList<ActiveMQXAResourceWrapperFactory>();
-      factories.add(new MockActiveMQResourceWrapperFactory());
-
-      Method method = ServiceUtils.class.getDeclaredMethod("setActiveMQXAResourceWrapperFactory", Iterable.class);
-      method.setAccessible(true);
-      method.invoke(null, factories);
-
-      Field field = ServiceUtils.class.getDeclaredField("activeMQXAResourceWrapperFactory");
-      field.setAccessible(true);
-      assertTrue(field.get(null) instanceof MockActiveMQResourceWrapperFactory);
    }
 }

artemis-service-extensions/src/test/resources/META-INF/services/org.apache.activemq.artemis.service.extensions.xa.ActiveMQXAResourceWrapperFactory

@@ -0,0 +1 @@
+org.apache.activemq.artemis.service.extensions.tests.xa.MockActiveMQResourceWrapperFactory