/*
 * Copyright 2007, 2008 (C) Tom Parker <thpr@users.sourceforge.net>
 * 
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 * 
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package pcgen.cdom.base;

import java.util.Collection;

import pcgen.cdom.enumeration.AssociationKey;

/**
 * SimpleAssociatedObject is a minimal implementation of the
 * AssociatedPrereqObject interface.
 */
public class SimpleAssociatedObject extends ConcretePrereqObject implements
		AssociatedPrereqObject
{

	/**
	 * Helper AssociationSupport to support the Association functions of this
	 * SimpleAssociatedObject
	 */
	private final AssociationSupport assoc = new AssociationSupport();

	/**
	 * Returns the value associated with the given AssociationKey. Returns null
	 * if this SimpleAssociatedObject contains no association for the given
	 * AssociationKey.
	 * 
	 * @param <T>
	 *            The type of the AssociationKey and the Class of the object to
	 *            be returned
	 * @param name
	 *            The AssociationKey for which the associated value is to be
	 *            returned
	 * @return The value associated with the given AssociationKey.
	 */
	@Override
	public <T> T getAssociation(AssociationKey<T> name)
	{
		return assoc.getAssociation(name);
	}

	/**
	 * Returns a Collection of the AssociationKeys that are in this
	 * SimpleAssociatedObject.
	 * 
	 * This method is value-semantic, meaning that ownership of the Collection
	 * returned by this method will be transferred to the calling object.
	 * Modification of the returned Collection should not result in modifying
	 * the SimpleAssociatedObject, and modifying the SimpleAssociatedObject
	 * after the Collection is returned should not modify the Collection.
	 * 
	 * Note that it may be possible for an association to have a null value.
	 * This method should include the AssociationKey for that association, if it
	 * is present in the SimpleAssociatedObject, even if the value of the
	 * association is null.
	 * 
	 * @return a Collection of the AssociationKeys that are in this
	 *         SimpleAssociatedObject.
	 */
	@Override
	public Collection<AssociationKey<?>> getAssociationKeys()
	{
		return assoc.getAssociationKeys();
	}

	/**
	 * Returns true if this SimpleAssociatedObject has any associations.
	 * 
	 * Note that it may be possible for an association to have a null value.
	 * This method should return true if the association is present, even if
	 * null.
	 * 
	 * @return true if this SimpleAssociatedObject has any associations; false
	 *         otherwise.
	 */
	@Override
	public boolean hasAssociations()
	{
		return assoc.hasAssociations();
	}

	/**
	 * Sets an Association (as defined by the given key) to the given value.
	 * Overwrites any previous value associated with the given AssociationKey.
	 * 
	 * @param <T>
	 *            The type of the AssociationKey and the Class of the object to
	 *            be associated with the given AssociationKey.
	 * @param name
	 *            The AssociationKey used to form the association with the given
	 *            value
	 * @param value
	 *            The value to be associated with the given AssociationKey
	 */
	@Override
	public <T> void setAssociation(AssociationKey<T> name, T value)
	{
		assoc.setAssociation(name, value);
	}

	/**
	 * Returns the consistent-with-equals hashCode for this
	 * SimpleAssociatedObject
	 * 
	 * @see java.lang.Object#hashCode()
	 */
	@Override
	public int hashCode()
	{
		return assoc.hashCode();
	}

	/**
	 * Returns true if this SimpleAssociatedObject is equal to the given Object.
	 * Equality is defined as being another SimpleAssociatedObject object with
	 * equal associations and Prerequisites.
	 * 
	 * @see java.lang.Object#equals(java.lang.Object)
	 */
	@Override
	public boolean equals(Object obj)
	{
		if (obj instanceof SimpleAssociatedObject)
		{
			SimpleAssociatedObject other = (SimpleAssociatedObject) obj;
			return assoc.equals(other.assoc) && equalsPrereqObject(other);
		}
		return false;
	}
}