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diff --git a/bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/baseadaptor/loader/ParallelClassLoader.java b/bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/baseadaptor/loader/ParallelClassLoader.java
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+/*******************************************************************************
+ * 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();
+}