| /******************************************************************************* |
| * Copyright (c) 2009 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.osgi.baseadaptor.loader; |
| |
| /** |
| * A parallel class loader. Parallel class loaders are thread safe class loaders |
| * which can handle multiple threads loading classes and resources from them at |
| * the same time. This is important for OSGi class loaders because the |
| * class loader delegate in OSGi is not strictly hierarchical, instead the |
| * delegation is grid based and may have cycles. |
| * <p> |
| * The {@link ClasspathManager} handles parallel capable class loaders |
| * differently from other class loaders. For parallel capable |
| * class loaders when {@link ClasspathManager#findLocalClass(String)} is |
| * called a lock will be obtained for the class name being searched while |
| * calling {@link BaseClassLoader#publicFindLoaded(String)} and |
| * {@link BaseClassLoader#defineClass(String, byte[], ClasspathEntry, org.eclipse.osgi.baseadaptor.bundlefile.BundleEntry)}. |
| * This prevents other threads from trying to searching for the same class at the |
| * same time. For other class loaders the class loader lock is obtained |
| * instead. This prevents other threads from trying to search for any |
| * class while the lock is held. |
| * </p> |
| * <p> |
| * <b>Note:</b> This interface is part of an interim API that is still under |
| * development. It is being made available at this early stage to solicit feedback |
| * from pioneering adopters on the understanding that any code that uses this API will may |
| * be broken (repeatedly) as the API evolves. |
| * </p> |
| * @since 3.5 |
| */ |
| public interface ParallelClassLoader extends BaseClassLoader { |
| /** |
| * Indicates if this class loader is parallel capable. Even |
| * if a class loader is able to be parallel capable there are some |
| * restrictions imposed by the VM which may prevent a class loader |
| * from being parallel capable. For example, some VMs may lock |
| * the class loader natively before delegating to a class loader. |
| * This type of locking will prevent a class loader from being |
| * parallel capable. |
| * @return true if this class loader is parallel capable; false otherwise. |
| */ |
| boolean isParallelCapable(); |
| } |
