org.eclipse.gemini.blueprint.context.support

Class TrackingUtil

java.lang.Object

org.eclipse.gemini.blueprint.context.support.TrackingUtil

abstract class TrackingUtil
extends java.lang.Object

Utility class for easy, but reliable, tracking of OSGi services. It does service tracking internally but wraps the logic into a proxy. Note that this class uses raw JDK proxies and thus is usable only with interfaces. This allows to create simple proxies with minimal class dependencies.

This class can be seen as a much shorter, less featured version of OsgiServiceProxyFactoryBean . It is intended for the bootstrap areas of the project where no classloading or listeners are required.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	TrackingUtil.OsgiServiceHandler JDK Proxy invocation handler that delegates all calls to services found in the OSGi space at the time of the call, falling back to a given object.

Constructor Summary

Constructors

Constructor and Description
TrackingUtil()

Method Summary

Modifier and Type	Method and Description
(package private) static java.lang.Object	getService(java.lang.Class<?>[] classes, java.lang.String filter, java.lang.ClassLoader classLoader, org.osgi.framework.BundleContext context, java.lang.Object fallbackObject) Returns a proxy that on each call seeks the relevant OSGi service and delegates the method invocation to it.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TrackingUtil

TrackingUtil()

Method Detail

getService

static java.lang.Object getService(java.lang.Class<?>[] classes,
                                   java.lang.String filter,
                                   java.lang.ClassLoader classLoader,
                                   org.osgi.framework.BundleContext context,
                                   java.lang.Object fallbackObject)

Returns a proxy that on each call seeks the relevant OSGi service and delegates the method invocation to it. In case no service is found, the fallback object is used.

Since JDK proxies are used to create services only interfaces are used.

Parameters:

classes - array of classes used during proxy weaving

filter - OSGi filter (can be null)

classLoader - class loader to use - normally classes.getClassLoader()

context - bundle context used for searching the services

fallbackObject - object to fall back onto if no OSGi service is found.

Returns:

the proxy doing the lookup on each method invocation