/******************************************************************************
* Copyright (c) 2006, 2010 VMware Inc., Oracle Inc.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Apache License v2.0 which accompanies this distribution.
* The Eclipse Public License is available at
* http://www.eclipse.org/legal/epl-v10.html and the Apache License v2.0
* is available at http://www.opensource.org/licenses/apache2.0.php.
* You may elect to redistribute this code under either of these licenses.
*
* Contributors:
* VMware Inc.
* Oracle Inc.
*****************************************************************************/
package org.eclipse.gemini.blueprint.service.importer.support;
import org.osgi.framework.BundleContext;
import org.springframework.core.NamedInheritableThreadLocal;
/**
* Class containing static methods used to obtain information about the current
* OSGi service invocation.
*
* <p>
* The <code>getInvokerBundleContext()</code> method offers access to the
* {@link BundleContext} of the entity accessing an OSGi service. The invoked
* entity can thus discover information about the caller context.
*
* <p>
* The functionality in this class might be used by a target object that needed
* access to resources on the invocation. However, this approach should not be
* used when there is a reasonable alternative, as it makes application code
* dependent on usage under AOP and the Spring Dynamic Modules and AOP framework
* in particular.
*
* @author Andy Piper
* @author Costin Leau
*/
public abstract class LocalBundleContext {
/**
* ThreadLocal holder for the invoker context.
*/
private final static ThreadLocal<BundleContext> invokerBundleContext = new NamedInheritableThreadLocal<BundleContext>(
"Current invoker bundle context");
/**
* Try to get the current invoker bundle context. Note that this can be
* <code>null</code> if the caller is not a Spring-DM importer.
*
* @return the invoker bundle context (can be null)
*/
public static BundleContext getInvokerBundleContext() {
return invokerBundleContext.get();
}
/**
* Set the invoker bundle context. Note that callers should take care in
* cleaning up the thread-local when the invocation ends.
*
* @param bundleContext invoker bundle context
* @return the old context in case there was one; maybe <code>null</code> is
* none is set
*/
static BundleContext setInvokerBundleContext(BundleContext bundleContext) {
BundleContext old = invokerBundleContext.get();
invokerBundleContext.set(bundleContext);
return old;
}
}