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

 /*
 * Copyright (c) 2020 Kentyou.
  * 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:
 *    Kentyou - initial API and implementation
  */

 package org.eclipse.sensinact.gateway.core;

 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;

 import org.eclipse.sensinact.gateway.common.bundle.Mediator;
 import org.eclipse.sensinact.gateway.common.constraint.Constraint;
 import org.eclipse.sensinact.gateway.common.primitive.DescribablePrimitive;
 import org.eclipse.sensinact.gateway.common.primitive.InvalidValueException;
 import org.eclipse.sensinact.gateway.common.primitive.Modifiable;
 import org.eclipse.sensinact.gateway.common.primitive.Name;
 import org.eclipse.sensinact.gateway.common.primitive.PrimitiveDescription;
 import org.eclipse.sensinact.gateway.util.CastUtils;
 import org.json.JSONArray;
 import org.json.JSONObject;

 /**
  * Extended {@link Primitive} defining an Attribute of a {@link Resource}
  *
  * @author <a href="mailto:christophe.munilla@cea.fr">Christophe Munilla</a>
  */
 public class Attribute extends DescribablePrimitive {
 	public static final String NICKNAME = "nickname";

 	/**
 	 * This Attribute's metadata.
 	 */
 	protected final List<Metadata> metadata;
 	private final ResourceImpl resource;
 	private int recipient;

 	/**
 	 * Constructor
 	 *
 	 * @param mediator
 	 *            the {@link Mediator} allowing the Attribute to be instantiated to
 	 *            interact with the OSGi host environment
 	 * @param resource
 	 *            the ResourceImpl holding the Attribute to be instantiated
 	 * @param name
 	 *            the name of the Attribute to instantiate
 	 * @param type
 	 *            the type of the Attribute to instantiate
 	 *
 	 * @throws InvalidValueException
 	 */
 	public Attribute(Mediator mediator, ResourceImpl resource, String name, Class<?> type)
 			throws InvalidValueException {
 		this(mediator, resource, name, type, null, Modifiable.UPDATABLE, false);
 		this.recipient = 0;
 	}

 	/**
 	 * Constructor
 	 *
 	 * @param mediator
 	 *            the {@link Mediator} allowing the Attribute to be instantiated to
 	 *            interact with the OSGi host environment
 	 * @param resource
 	 *            the ResourceImpl holding the Attribute to be instantiated
 	 * @param name
 	 *            the name of the Attribute to instantiate
 	 * @param type
 	 *            the type of the Attribute to instantiate
 	 * @param value
 	 *            the initial value of the Attribute to instantiate
 	 * @param modifiable
 	 *            is the value of Attribute to instantiate modifiable or not ?
 	 * @param hidden
 	 *            does the Attribute to instantiate provide its own JSON formated
 	 *            description or not
 	 *
 	 * @throws InvalidValueException
 	 */
 	public Attribute(Mediator mediator, ResourceImpl resource, String name, Class<?> type, Object value,
 			Modifiable modifiable, boolean hidden) throws InvalidValueException {
 		super(mediator, name, type);
 		this.resource = resource;
 		this.metadata = new ArrayList<Metadata>();

 		if (value != null) {
 			super.setValue(value);
 		}
 		Metadata modifiableMeta = new Metadata(super.mediator, Metadata.MODIFIABLE, Modifiable.class, modifiable,
 				Modifiable.FIXED);
 		this.addMetadata(modifiableMeta);

 		Metadata hiddenMeta = new Metadata(super.mediator, Metadata.HIDDEN, boolean.class, hidden, Modifiable.FIXED);
 		this.addMetadata(hiddenMeta);

 		Metadata timestampMeta = new Metadata(super.mediator, Metadata.TIMESTAMP, long.class,
 				System.currentTimeMillis(), Modifiable.UPDATABLE);
 		this.addMetadata(timestampMeta);

 		Metadata lockedMeta = new Metadata(super.mediator, Metadata.LOCKED, boolean.class, false, Modifiable.UPDATABLE);
 		this.addMetadata(lockedMeta);
 	}

 	/**
 	 * Constructs an attribute from the given {@link JSONObject} for the
 	 * ResourceImpl passed as parameter
 	 *
 	 * @param mediator the {@link Mediator} allowing the Attribute to be instantiated to
 	 * interact with the OSGi host environment
 	 * @param attribute the {@link JSONObject} describing the attribute to instantiate
 	 */
 	protected Attribute(Mediator mediator, ResourceImpl resource, JSONObject attribute) throws InvalidValueException {
 		super(mediator, attribute == null ? null : attribute.optString(PrimitiveDescription.NAME_KEY),
 				attribute == null ? null : attribute.optString(PrimitiveDescription.TYPE_KEY));

 		this.resource = resource;
 		this.metadata = new ArrayList<Metadata>();

 		// set the value if defined in the JSONObject
 		Object ovalue = attribute.opt(PrimitiveDescription.VALUE_KEY);

 		if (ovalue != null) {
 			this.setValue(CastUtils.getObjectFromJSON(super.mediator.getClassLoader(), this.getType(), ovalue));
 		}
 		JSONArray metadataArray = attribute.optJSONArray("metadata");

 		// adds Metadata specified in the JSON object if not null
 		if (metadataArray != null) {
 			int index = 0;
 			for (; index < metadataArray.length(); index++) {
 				Metadata metadata = new Metadata(super.mediator, metadataArray.getJSONObject(index));
 				this.addMetadata(metadata);
 			}
 		}
 		// modifiable Metadata added only if it does not already exist
 		// it is not overridden if defined as modifiable
 		if (!this.metadata.contains(new Name<Metadata>(Metadata.MODIFIABLE))) {
 			Metadata modifiableMeta = new Metadata(super.mediator, Metadata.MODIFIABLE, Modifiable.class,
 					Modifiable.MODIFIABLE, Modifiable.FIXED);
 			this.addMetadata(modifiableMeta);
 		}
 		// hidden Metadata added only if it does not already exist
 		// it is not overridden if defined as modifiable
 		if (!this.metadata.contains(new Name<Metadata>(Metadata.HIDDEN))) {
 			Metadata hiddenMeta = new Metadata(super.mediator, Metadata.HIDDEN, boolean.class, false, Modifiable.FIXED);
 			this.addMetadata(hiddenMeta);
 		}
 		if (!this.metadata.contains(new Name<Metadata>(Metadata.TIMESTAMP))) {
 			Metadata timestampMeta = new Metadata(super.mediator, Metadata.TIMESTAMP, long.class,
 					System.currentTimeMillis(), Modifiable.UPDATABLE);
 			this.addMetadata(timestampMeta);
 		}
 		if (!this.metadata.contains(new Name<Metadata>(Metadata.LOCKED))) {
 			Metadata lockedMeta = new Metadata(super.mediator, Metadata.LOCKED, boolean.class, false,
 					Modifiable.UPDATABLE);
 			this.addMetadata(lockedMeta);
 		}
 	}

 	/**
 	 * Defines the value of the {@link Metadata} whose whose name is passed as
 	 * parameter
 	 *
 	 * @param name the name of the {@link Metadata} to set the value of
 	 * @param value the value to set
 	 * @return the extended {@link Description} describing the modified Metadata
 	 * {@link Metadata}
 	 *
 	 * @throws InvalidValueException
 	 */
 	public MetadataDescription setMetadataValue(String name, Object value) throws InvalidValueException {
 		Metadata metadata = null;
 		if (name == null || (metadata = this.get(name)) == null)
 			return null;
 		metadata.setValue(value);
 		MetadataDescription description = (MetadataDescription) metadata.getDescription();
 		return description;
 	}

 	/**
 	 * Adds the {@link Metadata} passed as parameter to the list of ones owned by
 	 * this Attribute if it does not already exist or replaces the existing one with
 	 * the same name if it is defined as modifiable
 	 *
 	 * @param metadata the {@link Metadata} to add or update
 	 */
 	public void addMetadata(Metadata metadata) {
 		Metadata meta = this.get(metadata.getName());
 		synchronized (this.metadata) {
 			if (meta == null) {
 				this.metadata.add(metadata);
 				super.weakDescription = null;
 				if(!metadata.getName().equals(Metadata.HIDDEN) && metadata.getModifiable().equals(Modifiable.FIXED))
 					this.resource.updated(this, metadata.getDescription());
 			} else {
 				try {
 					this.setMetadataValue(metadata.getName(), metadata.getValue());
 				} catch (InvalidValueException e) {
 					if (super.mediator.isErrorLoggable())
 						super.mediator.error(e);
 				}
 				return;
 			}
 		}
 	}

 	/**
 	 * Removes the {@link Metadata} whose name is passed as parameter from the list
 	 * of ones owned by this Attribute if it exists
 	 *
 	 * @param metadata
 	 *            the name of the {@link Metadata} to remove
 	 * @return
 	 *         <ul>
 	 *         <li>true if the {@link Metadata} has been removed properly</li>
 	 *         <li>false if an error occurred or if the Metadata does not exist</li>
 	 *         </ul>
 	 */
 	public boolean removeMetadata(String metadata) {
 		if (metadata == null || Metadata.HIDDEN.intern() == metadata.intern()
 				|| Metadata.MODIFIABLE.intern() == metadata.intern() || Metadata.TIMESTAMP.intern() == metadata.intern()
 				|| Metadata.LOCKED.intern() == metadata.intern()) {
 			return false;
 		}
 		Metadata existingMeta = this.remove(metadata);
 		return (existingMeta != null);
 	}

 	/**
 	 * Sets this Primitive's value and defines the timestamp of the value change
 	 *
 	 * @param value
 	 *            the value to set
 	 * @param timestamp
 	 *            the timestamp of the value change
 	 *
 	 * @throws InvalidValueException
 	 *             if the value cannot be set
 	 */
 	@Override
 	public Object setValue(Object value) throws InvalidValueException {
 		return this.setValue(value, System.currentTimeMillis());
 	}

 	/**
 	 * Sets this Primitive's value and defines the timestamp of the value change
 	 *
 	 * @param value
 	 *            the value to set
 	 * @param timestamp
 	 *            the timestamp of the value change
 	 *
 	 * @throws InvalidValueException
 	 *             if the value cannot be set
 	 */
 	public Object setValue(Object value, long timestamp) throws InvalidValueException {
 		if (Modifiable.FIXED.equals(this.getModifiable())) {
 			throw new InvalidValueException("the value cannot be modified");
 		}
 		Object valueObject = cast(value);
 		Object copy = CastUtils.copy(super.type, valueObject);

 		synchronized (lock) {
 			boolean hasChanged = ((valueObject == null && super.value != null)
 					|| (valueObject != null && !valueObject.equals(super.value)));

 			this.beforeChange(copy);
 			this.setMetadataValue(Metadata.TIMESTAMP, timestamp);
 			super.value = valueObject;
 			this.afterChange(copy, hasChanged);
 		}
 		return copy;
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see Primitive#beforeChange(java.lang.Object)
 	 */
 	@Override
 	protected void beforeChange(Object value) throws InvalidValueException {
 		Metadata metadata = this.get(Metadata.CONSTRAINTS);
 		if (metadata == null) {
 			return;
 		}
 		Constraint[] constraints = null;
 		int length = 0;
 		try {
 			constraints = (Constraint[]) metadata.getValue();

 		} finally {
 			if (constraints == null || (length = constraints.length) == 0) {
 				return;
 			}
 		}
 		int index = 0;
 		for (; index < length; index++) {
 			if (!constraints[index].complies(value)) {
 				StringBuilder buffer = new StringBuilder();
 				buffer.append("value does not comply the constraint :");
 				buffer.append(constraints[index].getJSON());
 				String message = buffer.toString();
 				throw new InvalidValueException(message);
 			}
 		}
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see DescribablePrimitive# afterChange(java.lang.Object)
 	 *
 	 * @throws InvalidValueException
 	 */
 	private void afterChange(Object value, boolean hasChanged) throws InvalidValueException {
 		super.afterChange(value);
 		this.resource.updated(this, value, hasChanged);
 	}

 	/**
 	 * Defines the {@link ResourceImpl} to notify when the value of this Attribute
 	 * has changed
 	 *
 	 * @param recipient
 	 *            the change notifications recipient
 	 */
 	protected void addRecipient() {
 		this.recipient++;
 	}

 	/**
 	 * Defines the change notifications recipient as null
 	 */
 	protected void deleteRecipient() {
 		this.recipient--;
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see Primitive # createDescription(java.lang.String,java.lang.Class)
 	 */
 	@Override
 	protected AttributeDescription createDescription() {
 		AttributeDescription description = new AttributeDescription(this, this.getAllDescriptions());
 		return description;
 	}

 	/**
 	 * @inheritDoc
 	 *
 	 * @see Primitive #isModifiable()
 	 */
 	@Override
 	public Modifiable getModifiable() {
 		Modifiable modifiable = Modifiable.UPDATABLE;
 		Metadata metadata = null;

 		if ((metadata = this.get(Metadata.MODIFIABLE)) == null) {
 			return modifiable;
 		}
 		try {
 			modifiable = (Modifiable) metadata.getValue();

 		} catch (ClassCastException e) {
 			if (this.mediator.isErrorLoggable()) {
 				this.mediator.error(e, e.getMessage());
 			}
 		}
 		return modifiable;
 	}

 	/**
 	 * Returns true if this Attribute's value is locked; returns false otherwise
 	 *
 	 * @return
 	 *         <ul>
 	 *         <li>true is this Attribute's value is locked</li>
 	 *         <li>false otherwise</li>
 	 *         </ul>
 	 */
 	public boolean getLocked() {
 		boolean locked = false;
 		try {
 			locked = (Boolean) this.get(Metadata.LOCKED).getValue();

 		} catch (Exception e) {
 			this.mediator.error(e);
 		}
 		return locked;
 	}

 	/**
 	 * Defines this Attribute's value as locked
 	 */
 	protected void lock() {
 		try {
 			this.get(Metadata.LOCKED).setValue(true);

 		} catch (Exception e) {
 			this.mediator.error(e);
 		}
 	}

 	/**
 	 * Defines this Attribute value as unlocked
 	 */
 	protected void unlock() {
 		try {
 			this.get(Metadata.LOCKED).setValue(false);

 		} catch (Exception e) {
 			this.mediator.error(e);
 		}
 	}

 	/**
 	 * Returns true if this Attribute JSON description is hidden; returns false
 	 * otherwise
 	 *
 	 * @return
 	 *         <ul>
 	 *         <li>true if this Attribute JSON description is hidden;</li>
 	 *         <li>false otherwise</li>
 	 *         </ul>
 	 */
 	public boolean isHidden() {
 		Metadata metadata = this.get(Metadata.HIDDEN);
 		boolean hidden = false;
 		if (metadata != null) {
 			try {
 				hidden = ((Boolean) metadata.getValue()).booleanValue();

 			} catch (ClassCastException e) {
 				this.mediator.error(e, e.getMessage());
 			}
 		}
 		return hidden;
 	}

 	/**
 	 * Returns the {@link Metadata} of this Attribute, whose name is the same as the
 	 * specified one
 	 *
 	 * @param name
 	 *            the name of the searched {@link Metadata}
 	 * @return the {@link Metadata} with the specified name
 	 */
 	protected Metadata get(String name) {
 		int index = -1;
 		Metadata metadata = null;
 		synchronized (this.metadata) {
 			if ((index = this.metadata.indexOf(new Name<Attribute>(name))) != -1) {
 				metadata = this.metadata.get(index);
 			}
 		}
 		return metadata;
 	}

 	/**
 	 * Removes the {@link Metadata} whose name is passed as parameter
 	 *
 	 * @param primitive
 	 *            the name of the {@link Metadata} to remove
 	 * @return the removed {@link Metadata}
 	 */
 	private Metadata remove(String name) {
 		Metadata metadata = this.get(name);
 		if (metadata == null) {
 			synchronized (this.metadata) {
 				this.metadata.remove(metadata);
 				super.weakDescription = null;
 			}
 		}
 		return metadata;
 	}

 	/**
 	 * Returns the array of {@link MetadataDescription}s of all {@link Metadata} of
 	 * this Attribute
 	 *
 	 * @return the {@link MetadataDescription}s array of this Attribute
 	 */
 	public MetadataDescription[] getAllDescriptions() {
 		int index = 0;
 		MetadataDescription[] descriptions = new MetadataDescription[this.metadata.size()];

 		synchronized (this.metadata) {
 			Iterator<Metadata> iterator = this.metadata.iterator();
 			while (iterator.hasNext()) {
 				descriptions[index++] = iterator.next().getDescription();
 			}
 		}
 		return descriptions;
 	}
 }
	/*
	* Copyright (c) 2020 Kentyou.
	* 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:
	* Kentyou - initial API and implementation
	*/

	package org.eclipse.sensinact.gateway.core;

	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.List;

	import org.eclipse.sensinact.gateway.common.bundle.Mediator;
	import org.eclipse.sensinact.gateway.common.constraint.Constraint;
	import org.eclipse.sensinact.gateway.common.primitive.DescribablePrimitive;
	import org.eclipse.sensinact.gateway.common.primitive.InvalidValueException;
	import org.eclipse.sensinact.gateway.common.primitive.Modifiable;
	import org.eclipse.sensinact.gateway.common.primitive.Name;
	import org.eclipse.sensinact.gateway.common.primitive.PrimitiveDescription;
	import org.eclipse.sensinact.gateway.util.CastUtils;
	import org.json.JSONArray;
	import org.json.JSONObject;

	/**
	* Extended {@link Primitive} defining an Attribute of a {@link Resource}
	*
	* @author <a href="mailto:christophe.munilla@cea.fr">Christophe Munilla</a>
	*/
	public class Attribute extends DescribablePrimitive {
	public static final String NICKNAME = "nickname";

	/**
	* This Attribute's metadata.
	*/
	protected final List<Metadata> metadata;
	private final ResourceImpl resource;
	private int recipient;

	/**
	* Constructor
	*
	* @param mediator
	* the {@link Mediator} allowing the Attribute to be instantiated to
	* interact with the OSGi host environment
	* @param resource
	* the ResourceImpl holding the Attribute to be instantiated
	* @param name
	* the name of the Attribute to instantiate
	* @param type
	* the type of the Attribute to instantiate
	*
	* @throws InvalidValueException
	*/
	public Attribute(Mediator mediator, ResourceImpl resource, String name, Class<?> type)
	throws InvalidValueException {
	this(mediator, resource, name, type, null, Modifiable.UPDATABLE, false);
	this.recipient = 0;
	}

	/**
	* Constructor
	*
	* @param mediator
	* the {@link Mediator} allowing the Attribute to be instantiated to
	* interact with the OSGi host environment
	* @param resource
	* the ResourceImpl holding the Attribute to be instantiated
	* @param name
	* the name of the Attribute to instantiate
	* @param type
	* the type of the Attribute to instantiate
	* @param value
	* the initial value of the Attribute to instantiate
	* @param modifiable
	* is the value of Attribute to instantiate modifiable or not ?
	* @param hidden
	* does the Attribute to instantiate provide its own JSON formated
	* description or not
	*
	* @throws InvalidValueException
	*/
	public Attribute(Mediator mediator, ResourceImpl resource, String name, Class<?> type, Object value,
	Modifiable modifiable, boolean hidden) throws InvalidValueException {
	super(mediator, name, type);
	this.resource = resource;
	this.metadata = new ArrayList<Metadata>();

	if (value != null) {
	super.setValue(value);
	}
	Metadata modifiableMeta = new Metadata(super.mediator, Metadata.MODIFIABLE, Modifiable.class, modifiable,
	Modifiable.FIXED);
	this.addMetadata(modifiableMeta);

	Metadata hiddenMeta = new Metadata(super.mediator, Metadata.HIDDEN, boolean.class, hidden, Modifiable.FIXED);
	this.addMetadata(hiddenMeta);

	Metadata timestampMeta = new Metadata(super.mediator, Metadata.TIMESTAMP, long.class,
	System.currentTimeMillis(), Modifiable.UPDATABLE);
	this.addMetadata(timestampMeta);

	Metadata lockedMeta = new Metadata(super.mediator, Metadata.LOCKED, boolean.class, false, Modifiable.UPDATABLE);
	this.addMetadata(lockedMeta);
	}

	/**
	* Constructs an attribute from the given {@link JSONObject} for the
	* ResourceImpl passed as parameter
	*
	* @param mediator the {@link Mediator} allowing the Attribute to be instantiated to
	* interact with the OSGi host environment
	* @param attribute the {@link JSONObject} describing the attribute to instantiate
	*/
	protected Attribute(Mediator mediator, ResourceImpl resource, JSONObject attribute) throws InvalidValueException {
	super(mediator, attribute == null ? null : attribute.optString(PrimitiveDescription.NAME_KEY),
	attribute == null ? null : attribute.optString(PrimitiveDescription.TYPE_KEY));

	this.resource = resource;
	this.metadata = new ArrayList<Metadata>();

	// set the value if defined in the JSONObject
	Object ovalue = attribute.opt(PrimitiveDescription.VALUE_KEY);

	if (ovalue != null) {
	this.setValue(CastUtils.getObjectFromJSON(super.mediator.getClassLoader(), this.getType(), ovalue));
	}
	JSONArray metadataArray = attribute.optJSONArray("metadata");

	// adds Metadata specified in the JSON object if not null
	if (metadataArray != null) {
	int index = 0;
	for (; index < metadataArray.length(); index++) {
	Metadata metadata = new Metadata(super.mediator, metadataArray.getJSONObject(index));
	this.addMetadata(metadata);
	}
	}
	// modifiable Metadata added only if it does not already exist
	// it is not overridden if defined as modifiable
	if (!this.metadata.contains(new Name<Metadata>(Metadata.MODIFIABLE))) {
	Metadata modifiableMeta = new Metadata(super.mediator, Metadata.MODIFIABLE, Modifiable.class,
	Modifiable.MODIFIABLE, Modifiable.FIXED);
	this.addMetadata(modifiableMeta);
	}
	// hidden Metadata added only if it does not already exist
	// it is not overridden if defined as modifiable
	if (!this.metadata.contains(new Name<Metadata>(Metadata.HIDDEN))) {
	Metadata hiddenMeta = new Metadata(super.mediator, Metadata.HIDDEN, boolean.class, false, Modifiable.FIXED);
	this.addMetadata(hiddenMeta);
	}
	if (!this.metadata.contains(new Name<Metadata>(Metadata.TIMESTAMP))) {
	Metadata timestampMeta = new Metadata(super.mediator, Metadata.TIMESTAMP, long.class,
	System.currentTimeMillis(), Modifiable.UPDATABLE);
	this.addMetadata(timestampMeta);
	}
	if (!this.metadata.contains(new Name<Metadata>(Metadata.LOCKED))) {
	Metadata lockedMeta = new Metadata(super.mediator, Metadata.LOCKED, boolean.class, false,
	Modifiable.UPDATABLE);
	this.addMetadata(lockedMeta);
	}
	}

	/**
	* Defines the value of the {@link Metadata} whose whose name is passed as
	* parameter
	*
	* @param name the name of the {@link Metadata} to set the value of
	* @param value the value to set
	* @return the extended {@link Description} describing the modified Metadata
	* {@link Metadata}
	*
	* @throws InvalidValueException
	*/
	public MetadataDescription setMetadataValue(String name, Object value) throws InvalidValueException {
	Metadata metadata = null;
	if (name == null \|\| (metadata = this.get(name)) == null)
	return null;
	metadata.setValue(value);
	MetadataDescription description = (MetadataDescription) metadata.getDescription();
	return description;
	}

	/**
	* Adds the {@link Metadata} passed as parameter to the list of ones owned by
	* this Attribute if it does not already exist or replaces the existing one with
	* the same name if it is defined as modifiable
	*
	* @param metadata the {@link Metadata} to add or update
	*/
	public void addMetadata(Metadata metadata) {
	Metadata meta = this.get(metadata.getName());
	synchronized (this.metadata) {
	if (meta == null) {
	this.metadata.add(metadata);
	super.weakDescription = null;
	if(!metadata.getName().equals(Metadata.HIDDEN) && metadata.getModifiable().equals(Modifiable.FIXED))
	this.resource.updated(this, metadata.getDescription());
	} else {
	try {
	this.setMetadataValue(metadata.getName(), metadata.getValue());
	} catch (InvalidValueException e) {
	if (super.mediator.isErrorLoggable())
	super.mediator.error(e);
	}
	return;
	}
	}
	}

	/**
	* Removes the {@link Metadata} whose name is passed as parameter from the list
	* of ones owned by this Attribute if it exists
	*
	* @param metadata
	* the name of the {@link Metadata} to remove
	* @return
	* <ul>
	* <li>true if the {@link Metadata} has been removed properly</li>
	* <li>false if an error occurred or if the Metadata does not exist</li>
	* </ul>
	*/
	public boolean removeMetadata(String metadata) {
	if (metadata == null \|\| Metadata.HIDDEN.intern() == metadata.intern()
	\|\| Metadata.MODIFIABLE.intern() == metadata.intern() \|\| Metadata.TIMESTAMP.intern() == metadata.intern()
	\|\| Metadata.LOCKED.intern() == metadata.intern()) {
	return false;
	}
	Metadata existingMeta = this.remove(metadata);
	return (existingMeta != null);
	}

	/**
	* Sets this Primitive's value and defines the timestamp of the value change
	*
	* @param value
	* the value to set
	* @param timestamp
	* the timestamp of the value change
	*
	* @throws InvalidValueException
	* if the value cannot be set
	*/
	@Override
	public Object setValue(Object value) throws InvalidValueException {
	return this.setValue(value, System.currentTimeMillis());
	}

	/**
	* Sets this Primitive's value and defines the timestamp of the value change
	*
	* @param value
	* the value to set
	* @param timestamp
	* the timestamp of the value change
	*
	* @throws InvalidValueException
	* if the value cannot be set
	*/
	public Object setValue(Object value, long timestamp) throws InvalidValueException {
	if (Modifiable.FIXED.equals(this.getModifiable())) {
	throw new InvalidValueException("the value cannot be modified");
	}
	Object valueObject = cast(value);
	Object copy = CastUtils.copy(super.type, valueObject);

	synchronized (lock) {
	boolean hasChanged = ((valueObject == null && super.value != null)
	\|\| (valueObject != null && !valueObject.equals(super.value)));

	this.beforeChange(copy);
	this.setMetadataValue(Metadata.TIMESTAMP, timestamp);
	super.value = valueObject;
	this.afterChange(copy, hasChanged);
	}
	return copy;
	}

	/**
	* @inheritDoc
	*
	* @see Primitive#beforeChange(java.lang.Object)
	*/
	@Override
	protected void beforeChange(Object value) throws InvalidValueException {
	Metadata metadata = this.get(Metadata.CONSTRAINTS);
	if (metadata == null) {
	return;
	}
	Constraint[] constraints = null;
	int length = 0;
	try {
	constraints = (Constraint[]) metadata.getValue();

	} finally {
	if (constraints == null \|\| (length = constraints.length) == 0) {
	return;
	}
	}
	int index = 0;
	for (; index < length; index++) {
	if (!constraints[index].complies(value)) {
	StringBuilder buffer = new StringBuilder();
	buffer.append("value does not comply the constraint :");
	buffer.append(constraints[index].getJSON());
	String message = buffer.toString();
	throw new InvalidValueException(message);
	}
	}
	}

	/**
	* @inheritDoc
	*
	* @see DescribablePrimitive# afterChange(java.lang.Object)
	*
	* @throws InvalidValueException
	*/
	private void afterChange(Object value, boolean hasChanged) throws InvalidValueException {
	super.afterChange(value);
	this.resource.updated(this, value, hasChanged);
	}

	/**
	* Defines the {@link ResourceImpl} to notify when the value of this Attribute
	* has changed
	*
	* @param recipient
	* the change notifications recipient
	*/
	protected void addRecipient() {
	this.recipient++;
	}

	/**
	* Defines the change notifications recipient as null
	*/
	protected void deleteRecipient() {
	this.recipient--;
	}

	/**
	* @inheritDoc
	*
	* @see Primitive # createDescription(java.lang.String,java.lang.Class)
	*/
	@Override
	protected AttributeDescription createDescription() {
	AttributeDescription description = new AttributeDescription(this, this.getAllDescriptions());
	return description;
	}

	/**
	* @inheritDoc
	*
	* @see Primitive #isModifiable()
	*/
	@Override
	public Modifiable getModifiable() {
	Modifiable modifiable = Modifiable.UPDATABLE;
	Metadata metadata = null;

	if ((metadata = this.get(Metadata.MODIFIABLE)) == null) {
	return modifiable;
	}
	try {
	modifiable = (Modifiable) metadata.getValue();

	} catch (ClassCastException e) {
	if (this.mediator.isErrorLoggable()) {
	this.mediator.error(e, e.getMessage());
	}
	}
	return modifiable;
	}

	/**
	* Returns true if this Attribute's value is locked; returns false otherwise
	*
	* @return
	* <ul>
	* <li>true is this Attribute's value is locked</li>
	* <li>false otherwise</li>
	* </ul>
	*/
	public boolean getLocked() {
	boolean locked = false;
	try {
	locked = (Boolean) this.get(Metadata.LOCKED).getValue();

	} catch (Exception e) {
	this.mediator.error(e);
	}
	return locked;
	}

	/**
	* Defines this Attribute's value as locked
	*/
	protected void lock() {
	try {
	this.get(Metadata.LOCKED).setValue(true);

	} catch (Exception e) {
	this.mediator.error(e);
	}
	}

	/**
	* Defines this Attribute value as unlocked
	*/
	protected void unlock() {
	try {
	this.get(Metadata.LOCKED).setValue(false);

	} catch (Exception e) {
	this.mediator.error(e);
	}
	}

	/**
	* Returns true if this Attribute JSON description is hidden; returns false
	* otherwise
	*
	* @return
	* <ul>
	* <li>true if this Attribute JSON description is hidden;</li>
	* <li>false otherwise</li>
	* </ul>
	*/
	public boolean isHidden() {
	Metadata metadata = this.get(Metadata.HIDDEN);
	boolean hidden = false;
	if (metadata != null) {
	try {
	hidden = ((Boolean) metadata.getValue()).booleanValue();

	} catch (ClassCastException e) {
	this.mediator.error(e, e.getMessage());
	}
	}
	return hidden;
	}

	/**
	* Returns the {@link Metadata} of this Attribute, whose name is the same as the
	* specified one
	*
	* @param name
	* the name of the searched {@link Metadata}
	* @return the {@link Metadata} with the specified name
	*/
	protected Metadata get(String name) {
	int index = -1;
	Metadata metadata = null;
	synchronized (this.metadata) {
	if ((index = this.metadata.indexOf(new Name<Attribute>(name))) != -1) {
	metadata = this.metadata.get(index);
	}
	}
	return metadata;
	}

	/**
	* Removes the {@link Metadata} whose name is passed as parameter
	*
	* @param primitive
	* the name of the {@link Metadata} to remove
	* @return the removed {@link Metadata}
	*/
	private Metadata remove(String name) {
	Metadata metadata = this.get(name);
	if (metadata == null) {
	synchronized (this.metadata) {
	this.metadata.remove(metadata);
	super.weakDescription = null;
	}
	}
	return metadata;
	}

	/**
	* Returns the array of {@link MetadataDescription}s of all {@link Metadata} of
	* this Attribute
	*
	* @return the {@link MetadataDescription}s array of this Attribute
	*/
	public MetadataDescription[] getAllDescriptions() {
	int index = 0;
	MetadataDescription[] descriptions = new MetadataDescription[this.metadata.size()];

	synchronized (this.metadata) {
	Iterator<Metadata> iterator = this.metadata.iterator();
	while (iterator.hasNext()) {
	descriptions[index++] = iterator.next().getDescription();
	}
	}
	return descriptions;
	}
	}