svn commit: r1080927 - in /incubator/clerezza/trunk/parent/osgi.services: ./ src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala

[re...@apache.org]

Author: reto
Date: Sat Mar 12 12:16:36 2011
New Revision: 1080927

URL: http://svn.apache.org/viewvc?rev=1080927&view=rev
Log:
CLEREZZA-459: added doWith method for executing an action as soon as a service is available

Modified:
    incubator/clerezza/trunk/parent/osgi.services/   (props changed)
    incubator/clerezza/trunk/parent/osgi.services/src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala

Propchange: incubator/clerezza/trunk/parent/osgi.services/
------------------------------------------------------------------------------
--- svn:ignore (original)
+++ svn:ignore Sat Mar 12 12:16:36 2011
@@ -1,5 +1,8 @@
-target
 .classpath
-.project
 .externalToolBuilders
+.project
+target
+shell.iws
+shell.ipr
+shell.iml
 .settings

Modified: incubator/clerezza/trunk/parent/osgi.services/src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala
URL: http://svn.apache.org/viewvc/incubator/clerezza/trunk/parent/osgi.services/src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala?rev=1080927&r1=1080926&r2=1080927&view=diff
==============================================================================
--- incubator/clerezza/trunk/parent/osgi.services/src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala (original)
+++ incubator/clerezza/trunk/parent/osgi.services/src/main/scala/org/apache/clerezza/osgi/services/ServicesDsl.scala Sat Mar 12 12:16:36 2011
@@ -18,7 +18,7 @@
  */
 package org.apache.clerezza.osgi.services
 
-import org.osgi.framework.BundleContext
+import org.osgi.framework.{BundleContext, Constants, ServiceEvent, ServiceListener}
 import scala.collection.JavaConversions._
 
 class ServicesDsl(bundleContext: BundleContext) {
@@ -36,4 +36,29 @@ class ServicesDsl(bundleContext: BundleC
 			bundleContext.getService(serviceReference).asInstanceOf[T]
 		} else null.asInstanceOf[T]
 	}
+
+	/**
+	 * executes action as soon as a service exposing T is available, if such
+	 * a service is already available the action is executed immedtely and the
+	 * method blocks until the action finished executing, otherwise the method
+	 * returns and action will be executed when a respective becomes available.
+	 */
+	def doWith[T](action: T => Unit)(implicit m: Manifest[T]) {
+		val clazz = m.erasure.asInstanceOf[Class[T]]
+		val service = getService(clazz)
+		if (service != null) {
+			action(service)
+		} else {
+			lazy val serviceListener: ServiceListener = new ServiceListener {
+					def serviceChanged(e: ServiceEvent) = {
+						if (e.getType == ServiceEvent.REGISTERED) {
+							bundleContext.removeServiceListener(serviceListener)
+							action(bundleContext.getService(e.getServiceReference).asInstanceOf[T])
+						}
+					}
+				}
+			bundleContext.addServiceListener(serviceListener,
+											 "("+Constants.OBJECTCLASS+"="+clazz.getName+")")
+		}
+	}
 }