/**
* <copyright>
*
* Copyright (c) 2002-2006 IBM Corporation and others.
* 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:
* IBM - Initial API and implementation
*
* </copyright>
*
* $Id: AdapterFactoryImpl.java,v 1.6 2006/12/05 20:19:58 emerks Exp $
*/
package org.eclipse.emf.common.notify.impl;
import org.eclipse.emf.common.notify.Adapter;
import org.eclipse.emf.common.notify.AdapterFactory;
import org.eclipse.emf.common.notify.Notifier;
/**
* An extensible adapter factory implementation.
*/
public class AdapterFactoryImpl implements AdapterFactory
{
/**
* Creates an instance.
*/
public AdapterFactoryImpl()
{
super();
}
/**
* Returns <code>false</code>.
* @param type the key indicating the type of adapter in question.
* @return <code>false</code>.
*/
public boolean isFactoryForType(Object type)
{
return false;
}
/**
* Returns either
* the result of calling {@link #adapt(Notifier,Object) adapt(Notifier, Object)}
* or the result of calling {@link #resolve resolve(Object, Object)},
* depending on whether the target is a notifier.
* @param target arbitrary object to adapt.
* @param type the key indicating the type of adapter required.
* @return either an associated adapter or the object itself.
* @see #adapt(Notifier,Object)
* @see #resolve(Object, Object)
*/
public Object adapt(Object target, Object type)
{
if (target instanceof Notifier)
{
return adapt((Notifier)target, type);
}
else
{
return resolve(target, type);
}
}
/**
* Returns the object itself.
* This is called by {@link #adapt(Object,Object) adapt(Object, Object)} for objects that aren't notifiers.
* @param object arbitrary object to adapt.
* @param type the key indicating the type of adapter required.
* @return the object itself.
* @see #adapt(Object,Object)
*/
protected Object resolve(Object object, Object type)
{
return object;
}
public Adapter adapt(Notifier target, Object type)
{
for (Adapter adapter : target.eAdapters())
{
if (adapter.isAdapterForType(type))
{
return adapter;
}
}
return adaptNew(target, type);
}
/**
* Creates an adapter by calling {@link #createAdapter(Notifier, Object) createAdapter(Notifier, Object)}
* and associates it by calling {@link #associate(Adapter, Notifier) associate}.
* @param target the notifier to adapt.
* @param type the key indicating the type of adapter required.
* @return a new associated adapter.
* @see #createAdapter(Notifier, Object)
* @see #associate(Adapter, Notifier)
*/
public Adapter adaptNew(Notifier target, Object type)
{
Adapter adapter = createAdapter(target, type);
associate(adapter, target);
return adapter;
}
/**
* Creates an adapter by calling {@link #createAdapter(Notifier) createAdapter(Notifier)}
* and associates it by calling {@link #associate(Adapter, Notifier) associate}.
* @param target notifier to adapt.
* @see #createAdapter(Notifier)
*/
public void adaptAllNew(Notifier target)
{
Adapter adapter = createAdapter(target);
associate(adapter, target);
}
/**
* Creates an adapter by calling {@link #createAdapter(Notifier) createAdapter(Notifier)}.
* @param target the notifier to adapt.
* @param type the key indicating the type of adapter required.
* @return a new adapter.
* @see #createAdapter(Notifier)
*/
protected Adapter createAdapter(Notifier target, Object type)
{
return createAdapter(target);
}
/**
* Creates an {@link org.eclipse.emf.common.notify.impl.AdapterImpl}.
* @param target the notifier to adapt.
* @return a new adapter.
* @see #createAdapter(Notifier)
*/
protected Adapter createAdapter(Notifier target)
{
return new AdapterImpl();
}
/**
* Associates an adapter with a notifier by adding it to the target's {@link org.eclipse.emf.common.notify.Notifier#eAdapters adapters}.
* @param adapter the new adapter to associate.
* @param target the notifier being adapted.
*/
protected void associate(Adapter adapter, Notifier target)
{
if (adapter != null)
{
target.eAdapters().add(adapter);
}
}
}