platform/sensinact-core/src/main/java/org/eclipse/sensinact/gateway/core/ModelInstance.java - sensinact/org.eclipse.sensinact.gateway - Git at Google

 /*
  * Copyright (c) 2017 CEA.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *    CEA - initial API and implementation
  */
 package org.eclipse.sensinact.gateway.core;

 import java.security.AccessController;
 import java.security.PrivilegedAction;
 import java.util.Collection;
 import java.util.Dictionary;
 import java.util.Hashtable;
 import java.util.Iterator;
 import java.util.List;

 import org.eclipse.sensinact.gateway.api.core.AttributeBuilder;
 import org.eclipse.sensinact.gateway.api.core.Core;
 import org.eclipse.sensinact.gateway.api.core.DataResource;
 import org.eclipse.sensinact.gateway.api.core.ServiceProvider;
 import org.eclipse.sensinact.gateway.api.core.ServiceProvider.LifecycleStatus;
 import org.eclipse.sensinact.gateway.api.message.AbstractSnaMessage;
 import org.eclipse.sensinact.gateway.api.message.MessageCallback;
 import org.eclipse.sensinact.gateway.api.message.MessagePropagator;
 import org.eclipse.sensinact.gateway.api.message.SnaMessage;
 import org.eclipse.sensinact.gateway.common.bundle.Mediator;
 import org.eclipse.sensinact.gateway.common.execution.Executable;
 import org.eclipse.sensinact.gateway.common.primitive.Nameable;
 import org.eclipse.sensinact.gateway.common.primitive.ProcessableData;
 import org.eclipse.sensinact.gateway.core.message.MessageFilter;
 import org.eclipse.sensinact.gateway.core.message.SnaConstants;
 import org.eclipse.sensinact.gateway.core.method.AccessMethod;
 import org.eclipse.sensinact.gateway.core.security.AccessLevelOption;
 import org.eclipse.sensinact.gateway.core.security.AccessNode;
 import org.eclipse.sensinact.gateway.core.security.AccessNodeImpl;
 import org.eclipse.sensinact.gateway.core.security.MethodAccessibility;
 import org.eclipse.sensinact.gateway.security.signature.api.BundleValidation;
 import org.eclipse.sensinact.gateway.util.ReflectUtils;
 import org.eclipse.sensinact.gateway.util.UriUtils;
 import org.osgi.framework.InvalidSyntaxException;
 import org.osgi.framework.ServiceReference;
 import org.osgi.framework.ServiceRegistration;

 /**
  * A sensiNact Resource Model instance
  *
  * @author <a href="mailto:cmunilla@cmssi.fr">Christophe Munilla</a>
  */
 public class ModelInstance<C extends ModelConfiguration> implements SensiNactResourceModel<C>, LifecycleStatusListener {

 	/**
 	 * Returns the initial location of the sensiNact gateway and so of the service
 	 * providers for which it is not specified. This method should be called once at
 	 * initialization time
 	 *
 	 * @return the initial string location value ( latitude:longitude)
 	 */
 	public static String defaultLocation(Mediator mediator) {
 		double systemLatitude = 0d;
 		double systemLongitude = 0d;
 		try {
 			systemLatitude = Double.parseDouble(mediator.getContext().getProperty(ServiceProvider.LATITUDE_PROPERTY));
 			systemLongitude = Double.parseDouble(mediator.getContext().getProperty(ServiceProvider.LONGITUDE_PROPERTY));
 		} catch (Exception e) {
 			systemLatitude = ServiceProvider.DEFAULT_CEA_LOCATION_LATITUDE;
 			systemLongitude = ServiceProvider.DEFAULT_CEA_LOCATION_LONGITUDE;
 		}
 		String locationStr = new StringBuilder().append(systemLatitude).append(":").append(systemLongitude).toString();
 		return locationStr;
 	}

 	/**
 	 * the {@link Mediator} allowing to interact with the OSGi host environment
 	 */
 	protected Mediator mediator;

 	/**
 	 * the {@link SensiNactResourceModelConfiguration} of this ModelInstance
 	 */
 	protected final C configuration;

 	/**
 	 * the root {@link ServiceProviderImpl} of this instance of the sensiNact
 	 * resource model
 	 */
 	protected ServiceProviderImpl provider;

 	/**
 	 * <ul>
 	 * <li>true if this SensiNactResourceModel has been registered in the OSGi host
 	 * environment</li>
 	 * <li>false otherwise</li>
 	 * </ul>
 	 */
 	protected boolean registered;

 	/**
 	 * the String unique identifier of this SensiNactResourceModel in the OSGi host
 	 * environment
 	 */
 	private final String identifier;

 	/**
 	 * Remote ID of the sensiNact instance
 	 */
 	private String namespace;

 	/**
 	 * the {@link MesssageHandler} handling messages coming from this
 	 * SensiNactResourceModel
 	 */
 	protected MessagePropagator messageHandler;

 	/**
 	 * the String identifier of the profile of this SnaServiceProvider
 	 */
 	protected final String profileId;

 	/**
 	 * The {@link ServiceRegistration} in the OSGi host environment for this
 	 * {@link SensiNactResourceModel} instance
 	 */
 	private ModelInstanceRegistration registration;


 	/**
 	 * Constructor
 	 *
 	 * @param mediator
 	 *            the {@link Mediator} allowing to interact with the OSGi host
 	 *            environment
 	 * @param configuration
 	 *            the extended {@link ModelConfiguration} gathering the
 	 *            configuration properties applying on the ModelInstance to be
 	 *            created
 	 *
 	 * @throws InvalidServiceProviderException
 	 */
 	public ModelInstance(final Mediator mediator, C modelConfiguration, String name, String profileId)
 			throws InvalidServiceProviderException {
 		this.mediator = mediator;
 		this.profileId = profileId;
 		this.configuration = modelConfiguration;

 		List<String> initialSetOfServices = this.configuration.getFixedServices(name);
 		initialSetOfServices.addAll(this.configuration.getServices(profileId));

 		this.provider = ReflectUtils.getInstance(ServiceProviderImpl.class,
 			this.configuration.getProviderImplementationType(),
 			new Object[] { this, name, initialSetOfServices });

 		if (this.provider == null) {
 			throw new InvalidServiceProviderException("Unable to instantiate the root services provider");
 		}
 		// retrieve the unique identifier if it exits
 		this.identifier = this.mediator.callService(BundleValidation.class, new Executable<BundleValidation, String>() {
 			@Override
 			public String execute(BundleValidation service) throws Exception {
 				return service.check(mediator.getContext().getBundle());
 			}
 		});
 		this.namespace = this.mediator.callService(Core.class, new Executable<Core, String>() {
 			@Override
 			public String execute(Core core) throws Exception {
 				return core.namespace();
 			}
 		});
 	}


 	/**
 	 * @inheritDoc
 	 *
 	 * @see SensiNactResourceModel#configuration()
 	 */
 	@Override
 	public C configuration() {
 		return this.configuration;
 	}

 	/**
 	 * Returns a new {@link ServiceBuilder} instance
 	 *
 	 * @return a new {@link ServiceBuilder} instance
 	 */
 	public ServiceBuilder getServiceBuilder() {
 		ServiceBuilder builder = new ServiceBuilder(this.mediator, ServiceImpl.class);
 		builder.configureImplementationClass(this.configuration.getServiceImplementationType());
 		return builder;
 	}

 	/**
 	 * Returns a new {@link ResourceBuilder} parameterized by the
 	 * {@link ResourceConfig} passed as parameter
 	 *
 	 * @param resourceConfig
 	 *            the {@link ResourceConfig} parameterizing the
 	 *            {@link ResourceBuilder} to be created
 	 *
 	 * @return a new {@link ResourceBuilder} instance parameterized by the specified
 	 *         {@link ResourceConfig}
 	 */
 	public ResourceBuilder getResourceBuilder(ResourceConfig resourceConfig) {
 		ResourceBuilder builder = new ResourceBuilder(this.mediator, resourceConfig);
 		return builder;
 	}

 	/**
 	 *
 	 * @param descriptor
 	 * @param buildPolicy
 	 *
 	 * @return the appropriate {@link ResourceBuiler} according to the specified
 	 *         {@link ResourceDescriptor} and the build policy
 	 */
 	protected ResourceBuilder getResourceBuilder(ResourceDescriptor descriptor, byte buildPolicy) {
 		ResourceBuilder builder = null;

 		if (SensiNactResourceModelConfiguration.BuildPolicy.isBuildPolicy(buildPolicy,
 				SensiNactResourceModelConfiguration.BuildPolicy.BUILD_ON_DESCRIPTION)) {
 			builder = getResourceBuilder(descriptor);
 		}
 		if (builder == null && SensiNactResourceModelConfiguration.BuildPolicy.isBuildPolicy(buildPolicy,
 				SensiNactResourceModelConfiguration.BuildPolicy.BUILD_NON_DESCRIBED)) {
 			builder = createResourceBuilder(descriptor);
 		}
 		return builder;
 	}

 	/**
 	 * Returns a {@link ResourceBuilder} wrapping a previously registered
 	 * {@link ResourceConfig} for the {@link ResourceDescriptor} passed as
 	 * parameter. If no appropriate {@link ResourceConfig} can be retrieved, null is
 	 * returned
 	 *
 	 * @param descriptor
 	 *            the {@link ResourceDescriptor} describing the
 	 *            {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
 	 *            be returned
 	 *
 	 * @return a new {@link ResourceBuilder} instance
 	 */
 	public ResourceBuilder getResourceBuilder(ResourceDescriptor descriptor) {
 		ResourceConfig resourceConfig = this.configuration().getResourceConfig(descriptor);

 		if (resourceConfig == null) {
 			return null;
 		}
 		return configureResourceBuilder(resourceConfig, descriptor);
 	}

 	/**
 	 * Returns a {@link ResourceBuilder} wrapping a newly created
 	 * {@link ResourceConfig} for the {@link ResourceDescriptor} passed as
 	 * parameter. If no appropriate {@link ResourceConfig} can be created, null is
 	 * returned
 	 *
 	 * @param descriptor
 	 *            the {@link ResourceDescriptor} describing the
 	 *            {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
 	 *            be returned
 	 *
 	 * @return a new {@link ResourceBuilder} instance
 	 */
 	public ResourceBuilder createResourceBuilder(ResourceDescriptor descriptor) {
 		ResourceConfig resourceConfig = this.configuration().createResourceConfig(descriptor);
 		if (resourceConfig == null) {
 			return null;
 		}
 		return configureResourceBuilder(resourceConfig, descriptor);
 	}

 	/**
 	 * Returns a {@link ResourceBuilder} capable of creating a new resource based on
 	 * both the {@link ResourceConfig} and the {@link ResourceDescriptor} passed as
 	 * parameters
 	 *
 	 * @param resourceConfig
 	 *            the {@link ResourceConfig} that will be used by the
 	 *            {@link ResourceBuilder} to be returned
 	 * @param descriptor
 	 *            the {@link ResourceDescriptor} describing the
 	 *            {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
 	 *            be returned
 	 *
 	 * @return a new {@link ResourceBuilder} instance
 	 */
 	private <G extends ResourceConfig> ResourceBuilder configureResourceBuilder(G resourceConfig,
 			ResourceDescriptor descriptor) {
 		ResourceBuilder builder = new ResourceBuilder(this.mediator, resourceConfig);

 		if (descriptor.resourceName() != null) {
 			builder.configureName(descriptor.resourceName());
 		}
 		if (descriptor.dataType() != null) {
 			builder.configureType(descriptor.dataType());
 		}
 		if (descriptor.dataValue() != null) {
 			builder.configureValue(descriptor.dataValue());
 		}
 		if (descriptor.modifiable() != null) {
 			builder.configureRequirement(DataResource.VALUE, AttributeBuilder.Requirement.MODIFIABLE,
 					descriptor.modifiable());
 		}
 		if (descriptor.hidden() != null) {
 			builder.configureRequirement(DataResource.VALUE, AttributeBuilder.Requirement.HIDDEN,
 					descriptor.hidden().booleanValue());
 		}
 		return builder;
 	}

 	/**
 	 * Returns the {@link Mediator} of this SensiNactResourceModel allowing to
 	 * interact with the OSGi host environment
 	 *
 	 * @return this SensiNactResourceModel's {@link Mediator}
 	 */
 	public Mediator mediator() {
 		return this.mediator;
 	}

 	/**
 	 * Posts the {@link SnaMessage} past as parameter to the {@link MessagePropagator}
 	 * of this SensiNactResourceModel
 	 *
 	 * @param message
 	 *            the {@link SnaMessage} to post
 	 */
 	public void postMessage(SnaMessage<?> message) {
 		if (this.messageHandler == null) {
 			return;
 		}
 		((AbstractSnaMessage<?>)message).put("namespace", this.namespace, true);
 		this.messageHandler.propagate(message);
 	}

 	/**
 	 * Registers this sensiNact resource model instance in the OSGi host
 	 * environment.
 	 *
 	 * @throws ModelAlreadyRegisteredException
 	 *             if this sensiNact resource model instance is already registered
 	 */
 	protected final void register() throws ModelAlreadyRegisteredException {
 		if (this.registered) {
 			throw new ModelAlreadyRegisteredException(this.registration.getName());
 		}
 		final String name = this.getName();

 		boolean exists = AccessController.<Boolean>doPrivileged(new PrivilegedAction<Boolean>() {
 			@Override
 			public Boolean run() {
 				Collection<ServiceReference<SensiNactResourceModel>> references = null;
 				try {
 					references = ModelInstance.this.mediator.getContext().getServiceReferences(
 						SensiNactResourceModel.class, new StringBuilder().append("(name="
 							).append(name).append(")").toString());
 				} catch (InvalidSyntaxException e) {
 					ModelInstance.this.mediator.error(e);
 				}
 				return (references != null && references.size() > 0);
 			}
 		});
 		if (exists) {
 			throw new ModelAlreadyRegisteredException(name);
 		}
 		final String uri = UriUtils.getUri(new String[] { name });

 		final Dictionary<String, Object> props = new Hashtable<String, Object>();
 		props.put("name", name);

 		String location = null;
 		try {
 			location = this.getRootElement().getLocation();
 			props.put(SnaConstants.LOCATION, location);

 		} catch (NullPointerException e) {
 			mediator.debug(String.format("No initial location defined for %s", name));
 		}
 		AccessNode node = null;
 		AccessNode root = this.configuration.getAccessTree().getRoot();
 		AccessMethod.Type[] accessMethodTypes = AccessMethod.Type.values();
 		int typesLength = accessMethodTypes == null ? 0 : accessMethodTypes.length;
 		if ((node = (AccessNodeImpl<?>) root.get(uri)) == null) {
 			node = root;
 		}
 		int index = 0;
 		for (; index < typesLength; index++) {
 			AccessLevelOption accessLevelOption = node.getAccessLevelOption(accessMethodTypes[index]);
 			props.put(new StringBuilder().append(name).append(".").append(accessMethodTypes[index].name()).toString(),
 					accessLevelOption.getAccessLevel().getLevel());
 		}
 		ServiceRegistration<SensiNactResourceModel> instanceRegistration =
 			AccessController.<ServiceRegistration<SensiNactResourceModel>>doPrivileged(
 				new PrivilegedAction<ServiceRegistration<SensiNactResourceModel>>() {
 					@Override
 					public ServiceRegistration<SensiNactResourceModel> run() {
 						return ModelInstance.this.mediator.getContext(
 							).registerService(SensiNactResourceModel.class, ModelInstance.this, props);
 					}
 				});
 		if (instanceRegistration != null) {
 			this.registered = true;
 			List<String> observed = this.configuration.getObserved();

 			this.registration = new ModelInstanceRegistration(uri, observed, instanceRegistration, this.configuration);
 			this.messageHandler = new ModelInstanceMessagePropagator(mediator, this.configuration());

 			boolean pattern = false;

 			StringBuilder observedBuilder = new StringBuilder().append(uri);
 			if (observed != null && !observed.isEmpty()) {
 				observedBuilder.append("(/admin/location/value");
 				Iterator<String> it = observed.iterator();
 				while (it.hasNext()) {
 					String obs = null;
 					String[] uriElements = UriUtils.getUriElements(it.next());
 					switch (uriElements.length) {
 					case 0:
 					case 1:
 						continue;
 					case 2:
 						obs = UriUtils.getUri(uriElements).concat("/value");
 						break;
 					case 3:
 						obs = UriUtils.getUri(uriElements);
 						break;
 					default:
 						continue;
 					}
 					observedBuilder.append("|");
 					observedBuilder.append(obs);
 				}
 				observedBuilder.append(")");
 				pattern = true;
 			} else {
 				observedBuilder.append("/admin/location/value");
 			}
 			MessageFilter filter = new MessageFilter(mediator, observedBuilder.toString(), pattern, false);

 			filter.addHandledType(SnaMessage.Type.UPDATE);
 			this.messageHandler.addCallback(filter, registration);

 			filter = new MessageFilter(mediator, "(\\/[^\\/]+)+", true, false);
 			filter.addHandledType(SnaMessage.Type.LIFECYCLE);
 			this.messageHandler.addCallback(filter, registration);

 			if (this.configuration().getStartAtInitializationTime()) {
 				this.provider.start();
 			}
 		}
 	}

 	/**
 	 * Unregisters this sensiNact resource model instance from the OSGi host
 	 * environment
 	 *
 	 * @throws IllegalStateException
 	 *             if this sensiNact resource model instance is not registered
 	 */
 	public final void unregister() throws IllegalStateException {
 		if (!this.isRegistered()) {
 			throw new IllegalStateException(this.registration.getName());
 		}
 		this.registered = false;
 		try {
 			this.getRootElement().stop();

 		} catch (Exception e) {
 			mediator.error(e);
 		}
 		this.messageHandler.close(true);
 		this.messageHandler = null;

 		AccessController.<Void>doPrivileged(new PrivilegedAction<Void>() {
 			@Override
 			public Void run() {
 				ModelInstance.this.registration.unregister();
 				return null;
 			}
 		});
 	}

 	/**
 	 * Returns true if this SensiNactResourceModel has been registered; returns
 	 * false otherwise
 	 *
 	 * @return
 	 *         <ul>
 	 *         <li>true if this SensiNactResourceModel has already been
 	 *         registered</li>
 	 *         <li>false otherwise</li>
 	 *         </ul>
 	 */
 	public boolean isRegistered() {
 		return this.registered;
 	}

 	/**
 	 * Returns the root {@link ServiceProviderImpl} of this instance of the
 	 * sensiNact resource model
 	 *
 	 * @return this resource model instance's root {@link ServiceProviderImpl}
 	 *
 	 * @see SensiNactResourceModel#getRootElement()
 	 */
 	@Override
 	public ServiceProviderImpl getRootElement() {
 		return this.provider;
 	}

 	/**
 	 * @inheritedDoc
 	 *
 	 * @see Nameable#getName()
 	 */
 	@Override
 	public String getName() {
 		return this.getRootElement().getName();
 	}

 	/**
 	 * @inheritedDoc
 	 *
 	 * @see SensiNactResourceModel#getIdentifier()
 	 */
 	@Override
 	public String getIdentifier() {
 		return this.identifier;
 	}

 	/**
 	 * @param filter
 	 * @param callback
 	 */
 	public void registerCallback(MessageFilter filter, MessageCallback callback) {
 		if (this.messageHandler == null) {
 			return;
 		}
 		this.messageHandler.addCallback(filter, callback);
 	}

 	/**
 	 *
 	 * @param callback
 	 */
 	public void unregisterCallback(String callback) {
 		if (this.messageHandler == null) {
 			return;
 		}
 		this.messageHandler.deleteCallback(callback);
 	}

 	/**
 	 * Returns the string identifier of the profile to which this model instance
 	 * belongs to
 	 *
 	 * @return this model instance profile identifier
 	 */
 	public String getProfile() {
 		return this.profileId;
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see LifecycleStatusListener# update(ServiceProvider.LifecycleStatus)
 	 */
 	@Override
 	public void update(LifecycleStatus status) {
 		this.registration.updateLifecycle(status);
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see SensiNactResourceModel#getProperties()
 	 */
 	@Override
 	public Dictionary<String, String> getProperties() {
 		Dictionary<String, String> props = new Hashtable<String, String>();
 		props.put("uri", UriUtils.getUri(new String[] { this.getName() }));
 		props.put("lifecycle.status", this.getRootElement().getStatus().name());
 		return props;
 	}

 	/**
 	 * Returns the set of the specified {@link ModelElement} accessible
 	 * {@link AccessMethod.Type}s for the {@link AccessLevelOption} passed as
 	 * parameter and
 	 *
 	 * @param modelElement
 	 *            the {@link ModelElement} for which to retrieve the set of
 	 *            accessible {@link AccessMethod.Type}s
 	 * @param accessLevelOption
 	 *            the requirer {@link AccessLevelOption}
 	 *
 	 * @return the set of accessible {@link AccessMethod.Type} of the specified
 	 *         {@link ModelElement} for the specified {@link AccessLevelOption}
 	 */
 	public <I extends ModelInstance<?>, M extends ModelElementProxy, P extends ProcessableData, E extends Nameable, R extends Nameable> List<MethodAccessibility> getAuthorizations(
 			ModelElement<I, M, P, E, R> modelElement, AccessLevelOption accessLevelOption) {
 		if (modelElement.getModelInstance() != this) {
 			throw new RuntimeException("the model element argument must belong to this model instance");
 		}
 		final String path = modelElement.getPath();
 		return this.configuration().getAccessibleMethods(path, accessLevelOption);
 	}
 }
	/*
	* Copyright (c) 2017 CEA.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* CEA - initial API and implementation
	*/
	package org.eclipse.sensinact.gateway.core;

	import java.security.AccessController;
	import java.security.PrivilegedAction;
	import java.util.Collection;
	import java.util.Dictionary;
	import java.util.Hashtable;
	import java.util.Iterator;
	import java.util.List;

	import org.eclipse.sensinact.gateway.api.core.AttributeBuilder;
	import org.eclipse.sensinact.gateway.api.core.Core;
	import org.eclipse.sensinact.gateway.api.core.DataResource;
	import org.eclipse.sensinact.gateway.api.core.ServiceProvider;
	import org.eclipse.sensinact.gateway.api.core.ServiceProvider.LifecycleStatus;
	import org.eclipse.sensinact.gateway.api.message.AbstractSnaMessage;
	import org.eclipse.sensinact.gateway.api.message.MessageCallback;
	import org.eclipse.sensinact.gateway.api.message.MessagePropagator;
	import org.eclipse.sensinact.gateway.api.message.SnaMessage;
	import org.eclipse.sensinact.gateway.common.bundle.Mediator;
	import org.eclipse.sensinact.gateway.common.execution.Executable;
	import org.eclipse.sensinact.gateway.common.primitive.Nameable;
	import org.eclipse.sensinact.gateway.common.primitive.ProcessableData;
	import org.eclipse.sensinact.gateway.core.message.MessageFilter;
	import org.eclipse.sensinact.gateway.core.message.SnaConstants;
	import org.eclipse.sensinact.gateway.core.method.AccessMethod;
	import org.eclipse.sensinact.gateway.core.security.AccessLevelOption;
	import org.eclipse.sensinact.gateway.core.security.AccessNode;
	import org.eclipse.sensinact.gateway.core.security.AccessNodeImpl;
	import org.eclipse.sensinact.gateway.core.security.MethodAccessibility;
	import org.eclipse.sensinact.gateway.security.signature.api.BundleValidation;
	import org.eclipse.sensinact.gateway.util.ReflectUtils;
	import org.eclipse.sensinact.gateway.util.UriUtils;
	import org.osgi.framework.InvalidSyntaxException;
	import org.osgi.framework.ServiceReference;
	import org.osgi.framework.ServiceRegistration;

	/**
	* A sensiNact Resource Model instance
	*
	* @author <a href="mailto:cmunilla@cmssi.fr">Christophe Munilla</a>
	*/
	public class ModelInstance<C extends ModelConfiguration> implements SensiNactResourceModel<C>, LifecycleStatusListener {

	/**
	* Returns the initial location of the sensiNact gateway and so of the service
	* providers for which it is not specified. This method should be called once at
	* initialization time
	*
	* @return the initial string location value ( latitude:longitude)
	*/
	public static String defaultLocation(Mediator mediator) {
	double systemLatitude = 0d;
	double systemLongitude = 0d;
	try {
	systemLatitude = Double.parseDouble(mediator.getContext().getProperty(ServiceProvider.LATITUDE_PROPERTY));
	systemLongitude = Double.parseDouble(mediator.getContext().getProperty(ServiceProvider.LONGITUDE_PROPERTY));
	} catch (Exception e) {
	systemLatitude = ServiceProvider.DEFAULT_CEA_LOCATION_LATITUDE;
	systemLongitude = ServiceProvider.DEFAULT_CEA_LOCATION_LONGITUDE;
	}
	String locationStr = new StringBuilder().append(systemLatitude).append(":").append(systemLongitude).toString();
	return locationStr;
	}

	/**
	* the {@link Mediator} allowing to interact with the OSGi host environment
	*/
	protected Mediator mediator;

	/**
	* the {@link SensiNactResourceModelConfiguration} of this ModelInstance
	*/
	protected final C configuration;

	/**
	* the root {@link ServiceProviderImpl} of this instance of the sensiNact
	* resource model
	*/
	protected ServiceProviderImpl provider;

	/**
	* <ul>
	* <li>true if this SensiNactResourceModel has been registered in the OSGi host
	* environment</li>
	* <li>false otherwise</li>
	* </ul>
	*/
	protected boolean registered;

	/**
	* the String unique identifier of this SensiNactResourceModel in the OSGi host
	* environment
	*/
	private final String identifier;

	/**
	* Remote ID of the sensiNact instance
	*/
	private String namespace;

	/**
	* the {@link MesssageHandler} handling messages coming from this
	* SensiNactResourceModel
	*/
	protected MessagePropagator messageHandler;

	/**
	* the String identifier of the profile of this SnaServiceProvider
	*/
	protected final String profileId;

	/**
	* The {@link ServiceRegistration} in the OSGi host environment for this
	* {@link SensiNactResourceModel} instance
	*/
	private ModelInstanceRegistration registration;


	/**
	* Constructor
	*
	* @param mediator
	* the {@link Mediator} allowing to interact with the OSGi host
	* environment
	* @param configuration
	* the extended {@link ModelConfiguration} gathering the
	* configuration properties applying on the ModelInstance to be
	* created
	*
	* @throws InvalidServiceProviderException
	*/
	public ModelInstance(final Mediator mediator, C modelConfiguration, String name, String profileId)
	throws InvalidServiceProviderException {
	this.mediator = mediator;
	this.profileId = profileId;
	this.configuration = modelConfiguration;

	List<String> initialSetOfServices = this.configuration.getFixedServices(name);
	initialSetOfServices.addAll(this.configuration.getServices(profileId));

	this.provider = ReflectUtils.getInstance(ServiceProviderImpl.class,
	this.configuration.getProviderImplementationType(),
	new Object[] { this, name, initialSetOfServices });

	if (this.provider == null) {
	throw new InvalidServiceProviderException("Unable to instantiate the root services provider");
	}
	// retrieve the unique identifier if it exits
	this.identifier = this.mediator.callService(BundleValidation.class, new Executable<BundleValidation, String>() {
	@Override
	public String execute(BundleValidation service) throws Exception {
	return service.check(mediator.getContext().getBundle());
	}
	});
	this.namespace = this.mediator.callService(Core.class, new Executable<Core, String>() {
	@Override
	public String execute(Core core) throws Exception {
	return core.namespace();
	}
	});
	}


	/**
	* @inheritDoc
	*
	* @see SensiNactResourceModel#configuration()
	*/
	@Override
	public C configuration() {
	return this.configuration;
	}

	/**
	* Returns a new {@link ServiceBuilder} instance
	*
	* @return a new {@link ServiceBuilder} instance
	*/
	public ServiceBuilder getServiceBuilder() {
	ServiceBuilder builder = new ServiceBuilder(this.mediator, ServiceImpl.class);
	builder.configureImplementationClass(this.configuration.getServiceImplementationType());
	return builder;
	}

	/**
	* Returns a new {@link ResourceBuilder} parameterized by the
	* {@link ResourceConfig} passed as parameter
	*
	* @param resourceConfig
	* the {@link ResourceConfig} parameterizing the
	* {@link ResourceBuilder} to be created
	*
	* @return a new {@link ResourceBuilder} instance parameterized by the specified
	* {@link ResourceConfig}
	*/
	public ResourceBuilder getResourceBuilder(ResourceConfig resourceConfig) {
	ResourceBuilder builder = new ResourceBuilder(this.mediator, resourceConfig);
	return builder;
	}

	/**
	*
	* @param descriptor
	* @param buildPolicy
	*
	* @return the appropriate {@link ResourceBuiler} according to the specified
	* {@link ResourceDescriptor} and the build policy
	*/
	protected ResourceBuilder getResourceBuilder(ResourceDescriptor descriptor, byte buildPolicy) {
	ResourceBuilder builder = null;

	if (SensiNactResourceModelConfiguration.BuildPolicy.isBuildPolicy(buildPolicy,
	SensiNactResourceModelConfiguration.BuildPolicy.BUILD_ON_DESCRIPTION)) {
	builder = getResourceBuilder(descriptor);
	}
	if (builder == null && SensiNactResourceModelConfiguration.BuildPolicy.isBuildPolicy(buildPolicy,
	SensiNactResourceModelConfiguration.BuildPolicy.BUILD_NON_DESCRIBED)) {
	builder = createResourceBuilder(descriptor);
	}
	return builder;
	}

	/**
	* Returns a {@link ResourceBuilder} wrapping a previously registered
	* {@link ResourceConfig} for the {@link ResourceDescriptor} passed as
	* parameter. If no appropriate {@link ResourceConfig} can be retrieved, null is
	* returned
	*
	* @param descriptor
	* the {@link ResourceDescriptor} describing the
	* {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
	* be returned
	*
	* @return a new {@link ResourceBuilder} instance
	*/
	public ResourceBuilder getResourceBuilder(ResourceDescriptor descriptor) {
	ResourceConfig resourceConfig = this.configuration().getResourceConfig(descriptor);

	if (resourceConfig == null) {
	return null;
	}
	return configureResourceBuilder(resourceConfig, descriptor);
	}

	/**
	* Returns a {@link ResourceBuilder} wrapping a newly created
	* {@link ResourceConfig} for the {@link ResourceDescriptor} passed as
	* parameter. If no appropriate {@link ResourceConfig} can be created, null is
	* returned
	*
	* @param descriptor
	* the {@link ResourceDescriptor} describing the
	* {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
	* be returned
	*
	* @return a new {@link ResourceBuilder} instance
	*/
	public ResourceBuilder createResourceBuilder(ResourceDescriptor descriptor) {
	ResourceConfig resourceConfig = this.configuration().createResourceConfig(descriptor);
	if (resourceConfig == null) {
	return null;
	}
	return configureResourceBuilder(resourceConfig, descriptor);
	}

	/**
	* Returns a {@link ResourceBuilder} capable of creating a new resource based on
	* both the {@link ResourceConfig} and the {@link ResourceDescriptor} passed as
	* parameters
	*
	* @param resourceConfig
	* the {@link ResourceConfig} that will be used by the
	* {@link ResourceBuilder} to be returned
	* @param descriptor
	* the {@link ResourceDescriptor} describing the
	* {@link ResourceConfig} wrapped by the {@link ResourceBuilder} to
	* be returned
	*
	* @return a new {@link ResourceBuilder} instance
	*/
	private <G extends ResourceConfig> ResourceBuilder configureResourceBuilder(G resourceConfig,
	ResourceDescriptor descriptor) {
	ResourceBuilder builder = new ResourceBuilder(this.mediator, resourceConfig);

	if (descriptor.resourceName() != null) {
	builder.configureName(descriptor.resourceName());
	}
	if (descriptor.dataType() != null) {
	builder.configureType(descriptor.dataType());
	}
	if (descriptor.dataValue() != null) {
	builder.configureValue(descriptor.dataValue());
	}
	if (descriptor.modifiable() != null) {
	builder.configureRequirement(DataResource.VALUE, AttributeBuilder.Requirement.MODIFIABLE,
	descriptor.modifiable());
	}
	if (descriptor.hidden() != null) {
	builder.configureRequirement(DataResource.VALUE, AttributeBuilder.Requirement.HIDDEN,
	descriptor.hidden().booleanValue());
	}
	return builder;
	}

	/**
	* Returns the {@link Mediator} of this SensiNactResourceModel allowing to
	* interact with the OSGi host environment
	*
	* @return this SensiNactResourceModel's {@link Mediator}
	*/
	public Mediator mediator() {
	return this.mediator;
	}

	/**
	* Posts the {@link SnaMessage} past as parameter to the {@link MessagePropagator}
	* of this SensiNactResourceModel
	*
	* @param message
	* the {@link SnaMessage} to post
	*/
	public void postMessage(SnaMessage<?> message) {
	if (this.messageHandler == null) {
	return;
	}
	((AbstractSnaMessage<?>)message).put("namespace", this.namespace, true);
	this.messageHandler.propagate(message);
	}

	/**
	* Registers this sensiNact resource model instance in the OSGi host
	* environment.
	*
	* @throws ModelAlreadyRegisteredException
	* if this sensiNact resource model instance is already registered
	*/
	protected final void register() throws ModelAlreadyRegisteredException {
	if (this.registered) {
	throw new ModelAlreadyRegisteredException(this.registration.getName());
	}
	final String name = this.getName();

	boolean exists = AccessController.<Boolean>doPrivileged(new PrivilegedAction<Boolean>() {
	@Override
	public Boolean run() {
	Collection<ServiceReference<SensiNactResourceModel>> references = null;
	try {
	references = ModelInstance.this.mediator.getContext().getServiceReferences(
	SensiNactResourceModel.class, new StringBuilder().append("(name="
	).append(name).append(")").toString());
	} catch (InvalidSyntaxException e) {
	ModelInstance.this.mediator.error(e);
	}
	return (references != null && references.size() > 0);
	}
	});
	if (exists) {
	throw new ModelAlreadyRegisteredException(name);
	}
	final String uri = UriUtils.getUri(new String[] { name });

	final Dictionary<String, Object> props = new Hashtable<String, Object>();
	props.put("name", name);

	String location = null;
	try {
	location = this.getRootElement().getLocation();
	props.put(SnaConstants.LOCATION, location);

	} catch (NullPointerException e) {
	mediator.debug(String.format("No initial location defined for %s", name));
	}
	AccessNode node = null;
	AccessNode root = this.configuration.getAccessTree().getRoot();
	AccessMethod.Type[] accessMethodTypes = AccessMethod.Type.values();
	int typesLength = accessMethodTypes == null ? 0 : accessMethodTypes.length;
	if ((node = (AccessNodeImpl<?>) root.get(uri)) == null) {
	node = root;
	}
	int index = 0;
	for (; index < typesLength; index++) {
	AccessLevelOption accessLevelOption = node.getAccessLevelOption(accessMethodTypes[index]);
	props.put(new StringBuilder().append(name).append(".").append(accessMethodTypes[index].name()).toString(),
	accessLevelOption.getAccessLevel().getLevel());
	}
	ServiceRegistration<SensiNactResourceModel> instanceRegistration =
	AccessController.<ServiceRegistration<SensiNactResourceModel>>doPrivileged(
	new PrivilegedAction<ServiceRegistration<SensiNactResourceModel>>() {
	@Override
	public ServiceRegistration<SensiNactResourceModel> run() {
	return ModelInstance.this.mediator.getContext(
	).registerService(SensiNactResourceModel.class, ModelInstance.this, props);
	}
	});
	if (instanceRegistration != null) {
	this.registered = true;
	List<String> observed = this.configuration.getObserved();

	this.registration = new ModelInstanceRegistration(uri, observed, instanceRegistration, this.configuration);
	this.messageHandler = new ModelInstanceMessagePropagator(mediator, this.configuration());

	boolean pattern = false;

	StringBuilder observedBuilder = new StringBuilder().append(uri);
	if (observed != null && !observed.isEmpty()) {
	observedBuilder.append("(/admin/location/value");
	Iterator<String> it = observed.iterator();
	while (it.hasNext()) {
	String obs = null;
	String[] uriElements = UriUtils.getUriElements(it.next());
	switch (uriElements.length) {
	case 0:
	case 1:
	continue;
	case 2:
	obs = UriUtils.getUri(uriElements).concat("/value");
	break;
	case 3:
	obs = UriUtils.getUri(uriElements);
	break;
	default:
	continue;
	}
	observedBuilder.append("\|");
	observedBuilder.append(obs);
	}
	observedBuilder.append(")");
	pattern = true;
	} else {
	observedBuilder.append("/admin/location/value");
	}
	MessageFilter filter = new MessageFilter(mediator, observedBuilder.toString(), pattern, false);

	filter.addHandledType(SnaMessage.Type.UPDATE);
	this.messageHandler.addCallback(filter, registration);

	filter = new MessageFilter(mediator, "(\\/[^\\/]+)+", true, false);
	filter.addHandledType(SnaMessage.Type.LIFECYCLE);
	this.messageHandler.addCallback(filter, registration);

	if (this.configuration().getStartAtInitializationTime()) {
	this.provider.start();
	}
	}
	}

	/**
	* Unregisters this sensiNact resource model instance from the OSGi host
	* environment
	*
	* @throws IllegalStateException
	* if this sensiNact resource model instance is not registered
	*/
	public final void unregister() throws IllegalStateException {
	if (!this.isRegistered()) {
	throw new IllegalStateException(this.registration.getName());
	}
	this.registered = false;
	try {
	this.getRootElement().stop();

	} catch (Exception e) {
	mediator.error(e);
	}
	this.messageHandler.close(true);
	this.messageHandler = null;

	AccessController.<Void>doPrivileged(new PrivilegedAction<Void>() {
	@Override
	public Void run() {
	ModelInstance.this.registration.unregister();
	return null;
	}
	});
	}

	/**
	* Returns true if this SensiNactResourceModel has been registered; returns
	* false otherwise
	*
	* @return
	* <ul>
	* <li>true if this SensiNactResourceModel has already been
	* registered</li>
	* <li>false otherwise</li>
	* </ul>
	*/
	public boolean isRegistered() {
	return this.registered;
	}

	/**
	* Returns the root {@link ServiceProviderImpl} of this instance of the
	* sensiNact resource model
	*
	* @return this resource model instance's root {@link ServiceProviderImpl}
	*
	* @see SensiNactResourceModel#getRootElement()
	*/
	@Override
	public ServiceProviderImpl getRootElement() {
	return this.provider;
	}

	/**
	* @inheritedDoc
	*
	* @see Nameable#getName()
	*/
	@Override
	public String getName() {
	return this.getRootElement().getName();
	}

	/**
	* @inheritedDoc
	*
	* @see SensiNactResourceModel#getIdentifier()
	*/
	@Override
	public String getIdentifier() {
	return this.identifier;
	}

	/**
	* @param filter
	* @param callback
	*/
	public void registerCallback(MessageFilter filter, MessageCallback callback) {
	if (this.messageHandler == null) {
	return;
	}
	this.messageHandler.addCallback(filter, callback);
	}

	/**
	*
	* @param callback
	*/
	public void unregisterCallback(String callback) {
	if (this.messageHandler == null) {
	return;
	}
	this.messageHandler.deleteCallback(callback);
	}

	/**
	* Returns the string identifier of the profile to which this model instance
	* belongs to
	*
	* @return this model instance profile identifier
	*/
	public String getProfile() {
	return this.profileId;
	}

	/**
	* @inheritDoc
	*
	* @see LifecycleStatusListener# update(ServiceProvider.LifecycleStatus)
	*/
	@Override
	public void update(LifecycleStatus status) {
	this.registration.updateLifecycle(status);
	}

	/**
	* @inheritDoc
	*
	* @see SensiNactResourceModel#getProperties()
	*/
	@Override
	public Dictionary<String, String> getProperties() {
	Dictionary<String, String> props = new Hashtable<String, String>();
	props.put("uri", UriUtils.getUri(new String[] { this.getName() }));
	props.put("lifecycle.status", this.getRootElement().getStatus().name());
	return props;
	}

	/**
	* Returns the set of the specified {@link ModelElement} accessible
	* {@link AccessMethod.Type}s for the {@link AccessLevelOption} passed as
	* parameter and
	*
	* @param modelElement
	* the {@link ModelElement} for which to retrieve the set of
	* accessible {@link AccessMethod.Type}s
	* @param accessLevelOption
	* the requirer {@link AccessLevelOption}
	*
	* @return the set of accessible {@link AccessMethod.Type} of the specified
	* {@link ModelElement} for the specified {@link AccessLevelOption}
	*/
	public <I extends ModelInstance<?>, M extends ModelElementProxy, P extends ProcessableData, E extends Nameable, R extends Nameable> List<MethodAccessibility> getAuthorizations(
	ModelElement<I, M, P, E, R> modelElement, AccessLevelOption accessLevelOption) {
	if (modelElement.getModelInstance() != this) {
	throw new RuntimeException("the model element argument must belong to this model instance");
	}
	final String path = modelElement.getPath();
	return this.configuration().getAccessibleMethods(path, accessLevelOption);
	}
	}