binding/mdsal-binding-dom-codec-osgi/src/main/java/org/opendaylight/mdsal/binding/dom/codec/osgi/impl/OSGiBindingDOMCodec.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.codec.osgi.impl;
   9
  10 import static com.google.common.base.Verify.verify;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import java.util.Collections;
  14 import java.util.Comparator;
  15 import java.util.IdentityHashMap;
  16 import java.util.Map;
  17 import java.util.Set;
  18 import org.checkerframework.checker.lock.qual.GuardedBy;
  19 import org.eclipse.jdt.annotation.NonNull;
  20 import org.opendaylight.mdsal.binding.dom.codec.osgi.OSGiBindingDOMCodecServices;
  21 import org.opendaylight.mdsal.binding.dom.codec.spi.BindingDOMCodecFactory;
  22 import org.opendaylight.mdsal.binding.runtime.api.BindingRuntimeContext;
  23 import org.opendaylight.mdsal.binding.runtime.osgi.OSGiBindingRuntimeContext;
  24 import org.osgi.service.component.ComponentFactory;
  25 import org.osgi.service.component.ComponentInstance;
  26 import org.osgi.service.component.annotations.Activate;
  27 import org.osgi.service.component.annotations.Component;
  28 import org.osgi.service.component.annotations.Deactivate;
  29 import org.osgi.service.component.annotations.Reference;
  30 import org.osgi.service.component.annotations.ReferenceCardinality;
  31 import org.osgi.service.component.annotations.ReferencePolicy;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34
  35 @Component(immediate = true)
  36 public final class OSGiBindingDOMCodec {
  37     // TODO: can we get rid of this complexity?
  38     private abstract static class AbstractInstances {
  39
  40         abstract void add(OSGiBindingRuntimeContext runtimeContext);
  41
  42         abstract void remove(OSGiBindingRuntimeContext runtimeContext);
  43
  44         abstract @NonNull AbstractInstances toActive(BindingDOMCodecFactory codecFactory,
  45             ComponentFactory<OSGiBindingDOMCodecServices> factory);
  46
  47         abstract @NonNull AbstractInstances toInactive();
  48     }
  49
  50     private static final class InactiveInstances extends AbstractInstances {
  51         private final Set<OSGiBindingRuntimeContext> instances = Collections.newSetFromMap(new IdentityHashMap<>());
  52
  53         InactiveInstances() {
  54
  55         }
  56
  57         InactiveInstances(final Set<OSGiBindingRuntimeContext> keySet) {
  58             instances.addAll(keySet);
  59         }
  60
  61         @Override
  62         void add(final OSGiBindingRuntimeContext runtimeContext) {
  63             verify(instances.add(runtimeContext), "Duplicate instance %s?!", runtimeContext);
  64         }
  65
  66         @Override
  67         void remove(final OSGiBindingRuntimeContext runtimeContext) {
  68             instances.remove(runtimeContext);
  69         }
  70
  71         @Override
  72         AbstractInstances toActive(final BindingDOMCodecFactory codecFactory,
  73                 final ComponentFactory<OSGiBindingDOMCodecServices> factory) {
  74             final ActiveInstances active = new ActiveInstances(codecFactory, factory);
  75             instances.stream()
  76                 .sorted(Comparator.comparing(OSGiBindingRuntimeContext::getGeneration).reversed())
  77                 .forEach(active::add);
  78             return active;
  79         }
  80
  81         @Override
  82         AbstractInstances toInactive() {
  83             throw new IllegalStateException("Attempted to deactivate inactive instances");
  84         }
  85     }
  86
  87     private static final class ActiveInstances extends AbstractInstances {
  88         private final Map<OSGiBindingRuntimeContext, ComponentInstance<OSGiBindingDOMCodecServices>> instances =
  89             new IdentityHashMap<>();
  90         private final ComponentFactory<OSGiBindingDOMCodecServices> factory;
  91         private final BindingDOMCodecFactory codecFactory;
  92
  93         ActiveInstances(final BindingDOMCodecFactory codecFactory,
  94                 final ComponentFactory<OSGiBindingDOMCodecServices> factory) {
  95             this.codecFactory = requireNonNull(codecFactory);
  96             this.factory = requireNonNull(factory);
  97         }
  98
  99         @Override
 100         void add(final OSGiBindingRuntimeContext runtimeContext) {
 101             final BindingRuntimeContext context = runtimeContext.getService();
 102
 103             instances.put(runtimeContext, factory.newInstance(OSGiBindingDOMCodecServicesImpl.props(
 104                 runtimeContext.getGeneration(), runtimeContext.getServiceRanking(),
 105                 codecFactory.createBindingDOMCodec(context))));
 106         }
 107
 108         @Override
 109         void remove(final OSGiBindingRuntimeContext runtimeContext) {
 110             final ComponentInstance<OSGiBindingDOMCodecServices> instance = instances.remove(runtimeContext);
 111             if (instance != null) {
 112                 instance.dispose();
 113             } else {
 114                 LOG.warn("Instance for generation {} not found", runtimeContext.getGeneration());
 115             }
 116         }
 117
 118         @Override
 119         AbstractInstances toActive(final BindingDOMCodecFactory ignoreCodecFactory,
 120                 final ComponentFactory<OSGiBindingDOMCodecServices> ignoreFactory) {
 121             throw new IllegalStateException("Attempted to activate active instances");
 122         }
 123
 124         @Override
 125         AbstractInstances toInactive() {
 126             instances.values().forEach(ComponentInstance::dispose);
 127             return new InactiveInstances(instances.keySet());
 128         }
 129
 130     }
 131
 132     private static final Logger LOG = LoggerFactory.getLogger(OSGiBindingDOMCodec.class);
 133
 134     @Reference
 135     BindingDOMCodecFactory codecFactory = null;
 136
 137     @Reference(target = "(component.factory=" + OSGiBindingDOMCodecServicesImpl.FACTORY_NAME + ")")
 138     ComponentFactory<OSGiBindingDOMCodecServices> contextFactory = null;
 139
 140     @GuardedBy("this")
 141     private AbstractInstances instances = new InactiveInstances();
 142
 143     @Reference(cardinality = ReferenceCardinality.MULTIPLE, policy = ReferencePolicy.DYNAMIC)
 144     synchronized void addModuleInfoSnapshot(final OSGiBindingRuntimeContext runtimeContext) {
 145         instances.add(runtimeContext);
 146     }
 147
 148     synchronized void removeModuleInfoSnapshot(final OSGiBindingRuntimeContext runtimeContext) {
 149         instances.remove(runtimeContext);
 150     }
 151
 152     @Activate
 153     synchronized void activate() {
 154         LOG.info("Binding/DOM Codec activating");
 155         instances = instances.toActive(codecFactory, contextFactory);
 156         LOG.info("Binding/DOM Codec activated");
 157     }
 158
 159     @Deactivate
 160     synchronized void deactivate() {
 161         LOG.info("Binding/DOM Codec deactivating");
 162         instances = instances.toInactive();
 163         LOG.info("Binding/DOM Codec deactivated");
 164     }
 165 }