opendaylight/config/config-manager/src/main/java/org/opendaylight/controller/config/manager/impl/osgi/BeanToOsgiServiceManager.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. 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.controller.config.manager.impl.osgi;
   9
  10 import org.opendaylight.controller.config.api.ModuleIdentifier;
  11 import org.opendaylight.controller.config.api.annotations.ServiceInterfaceAnnotation;
  12 import org.opendaylight.controller.config.manager.impl.util.InterfacesHelper;
  13 import org.opendaylight.controller.config.spi.Module;
  14 import org.osgi.framework.BundleContext;
  15 import org.osgi.framework.ServiceRegistration;
  16
  17 import java.util.Dictionary;
  18 import java.util.HashSet;
  19 import java.util.Hashtable;
  20 import java.util.Set;
  21
  22 /**
  23  * Registers instantiated beans as OSGi services and unregisters these services
  24  * if beans are destroyed.
  25  */
  26 public class BeanToOsgiServiceManager {
  27     // name of properties submitted to osgi
  28     static final String INSTANCE_NAME_OSGI_PROP = "instanceName";
  29     static final String IMPLEMENTATION_NAME_OSGI_PROP = "implementationName";
  30
  31     /**
  32      * To be called for every created, reconfigured and recreated config bean.
  33      * It is expected that before using this method OSGi service registry will
  34      * be cleaned from previous registrations.
  35      */
  36     public OsgiRegistration registerToOsgi(
  37             Class<? extends Module> configBeanClass, AutoCloseable instance,
  38             ModuleIdentifier moduleIdentifier, BundleContext bundleContext) {
  39         try {
  40             final Set<Class<?>> configuresInterfaces = InterfacesHelper
  41                     .getOsgiRegistrationTypes(configBeanClass);
  42             checkInstanceImplementing(instance, configuresInterfaces);
  43
  44             // bundleContext.registerService blows up with empty 'clazzes'
  45             if (configuresInterfaces.isEmpty() == false) {
  46                 final Dictionary<String, ?> propertiesForOsgi = getPropertiesForOsgi(moduleIdentifier);
  47                 final ServiceRegistration<?> serviceRegistration = bundleContext
  48                         .registerService(classesToNames(configuresInterfaces), instance, propertiesForOsgi);
  49                 return new OsgiRegistration(serviceRegistration);
  50             } else {
  51                 return new OsgiRegistration();
  52             }
  53         } catch (IllegalStateException e) {
  54             throw new IllegalStateException(
  55                     "Error while registering instance into OSGi Service Registry: "
  56                             + moduleIdentifier, e);
  57         }
  58     }
  59
  60     private static String[] classesToNames(Set<Class<?>> cfgs) {
  61         String[] result = new String[cfgs.size()];
  62         int i = 0;
  63         for (Class<?> cfg : cfgs) {
  64             result[i] = cfg.getName();
  65             i++;
  66         }
  67         return result;
  68     }
  69
  70     private void checkInstanceImplementing(AutoCloseable instance,
  71             Set<Class<?>> configures) {
  72         Set<Class<?>> missing = new HashSet<>();
  73         for (Class<?> requiredIfc : configures) {
  74             if (requiredIfc.isInstance(instance) == false) {
  75                 missing.add(requiredIfc);
  76             }
  77         }
  78         if (missing.isEmpty() == false) {
  79             throw new IllegalStateException(
  80                     instance.getClass()
  81                             + " does not implement following interfaces as announced by "
  82                             + ServiceInterfaceAnnotation.class.getName()
  83                             + " annotation :" + missing);
  84         }
  85     }
  86
  87     private static Dictionary<String, ?> getPropertiesForOsgi(
  88             ModuleIdentifier moduleIdentifier) {
  89         Hashtable<String, String> table = new Hashtable<>();
  90         table.put(IMPLEMENTATION_NAME_OSGI_PROP,
  91                 moduleIdentifier.getFactoryName());
  92         table.put(INSTANCE_NAME_OSGI_PROP, moduleIdentifier.getInstanceName());
  93         return table;
  94     }
  95
  96     public static class OsgiRegistration implements AutoCloseable {
  97         private final ServiceRegistration<?> serviceRegistration;
  98
  99         public OsgiRegistration(ServiceRegistration<?> serviceRegistration) {
 100             this.serviceRegistration = serviceRegistration;
 101         }
 102
 103         public OsgiRegistration() {
 104             this.serviceRegistration = null;
 105         }
 106
 107         @Override
 108         public void close() {
 109             if (serviceRegistration != null) {
 110                 serviceRegistration.unregister();
 111             }
 112         }
 113     }
 114
 115 }