binding/mdsal-binding-dom-adapter/src/main/java/org/opendaylight/mdsal/binding/dom/adapter/osgi/AdaptingTracker.java

   1 /*
   2  * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.mdsal.binding.dom.adapter.osgi;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import java.util.function.Function;
  13 import org.eclipse.jdt.annotation.NonNull;
  14 import org.opendaylight.mdsal.binding.api.BindingService;
  15 import org.opendaylight.mdsal.dom.api.DOMService;
  16 import org.osgi.framework.BundleContext;
  17 import org.osgi.framework.ServiceReference;
  18 import org.osgi.service.component.ComponentFactory;
  19 import org.osgi.service.component.ComponentInstance;
  20 import org.osgi.util.tracker.ServiceTracker;
  21 import org.slf4j.Logger;
  22 import org.slf4j.LoggerFactory;
  23
  24 /**
  25  * A ServiceTracker which adapts a DOMService to a BindingService.
  26  *
  27  * @param <D> DOMService type
  28  * @param <B> BindingService type
  29  * @author Robert Varga
  30  */
  31 final class AdaptingTracker<D extends DOMService, B extends BindingService>
  32         extends ServiceTracker<D, AdaptingTracker.ComponentHolder<B>> {
  33     static final class ComponentHolder<B extends BindingService> {
  34         final B binding;
  35         ComponentInstance<? extends B> component;
  36
  37         ComponentHolder(final B binding, final ComponentInstance<? extends B> component) {
  38             this.binding = requireNonNull(binding);
  39             this.component = requireNonNull(component);
  40         }
  41     }
  42
  43     private static final Logger LOG = LoggerFactory.getLogger(AdaptingTracker.class);
  44
  45     private final Function<D, B> bindingFactory;
  46     private final @NonNull Class<B> bindingClass;
  47     private final ComponentFactory<? extends B> componentFactory;
  48
  49     AdaptingTracker(final BundleContext ctx, final Class<D> domClass, final Class<B> bindingClass,
  50             final Function<D, B> bindingFactory, final ComponentFactory<? extends B> componentFactory) {
  51         super(ctx, domClass, null);
  52         this.bindingClass = requireNonNull(bindingClass);
  53         this.bindingFactory = requireNonNull(bindingFactory);
  54         this.componentFactory = requireNonNull(componentFactory);
  55     }
  56
  57     @Override
  58     public void open(final boolean trackAllServices) {
  59         LOG.debug("Starting tracker for {}", bindingClass.getName());
  60         super.open(trackAllServices);
  61         LOG.debug("Tracker for {} started", bindingClass.getName());
  62     }
  63
  64     @Override
  65     public ComponentHolder<B> addingService(final ServiceReference<D> reference) {
  66         if (reference == null) {
  67             LOG.debug("Null reference for {}, ignoring it", bindingClass.getName());
  68             return null;
  69         }
  70         if (reference.getProperty(ServiceProperties.IGNORE_PROP) != null) {
  71             LOG.debug("Ignoring reference {} due to {}", reference, ServiceProperties.IGNORE_PROP);
  72             return null;
  73         }
  74
  75         final D dom = context.getService(reference);
  76         if (dom == null) {
  77             LOG.debug("Could not get {} service from {}, ignoring it", bindingClass.getName(), reference);
  78             return null;
  79         }
  80
  81         final B binding = bindingFactory.apply(dom);
  82         return new ComponentHolder<>(binding, componentFactory.newInstance(Dict.fromReference(reference, binding)));
  83     }
  84
  85     @Override
  86     public void modifiedService(final ServiceReference<D> reference, final ComponentHolder<B> service) {
  87         if (service != null && reference != null) {
  88             service.component.dispose();
  89             service.component = componentFactory.newInstance(Dict.fromReference(reference, service.binding));
  90         }
  91     }
  92
  93     @Override
  94     public void removedService(final ServiceReference<D> reference, final ComponentHolder<B> service) {
  95         if (service != null) {
  96             context.ungetService(reference);
  97             service.component.dispose();
  98             LOG.debug("Unregistered service {}", service);
  99         }
 100     }
 101 }