/*******************************************************************************
* Copyright (c) 2005 Oracle Corporation.
* 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:
* Ian Trimble - initial API and implementation
*******************************************************************************/
package org.eclipse.jst.tapestry.core.internal.tapestrylibraryregistry.adapter;
import org.eclipse.emf.common.notify.Notification;
import org.eclipse.emf.common.notify.impl.AdapterImpl;
import org.eclipse.emf.common.util.EList;
import org.eclipse.jst.tapestry.core.internal.tapestrylibraryconfig.TapestryLibraryRegistryUtil;
import org.eclipse.jst.tapestry.core.internal.tapestrylibraryregistry.TapestryLibrary;
import org.eclipse.jst.tapestry.core.internal.tapestrylibraryregistry.TapestryLibraryRegistry;
import org.eclipse.jst.tapestry.core.internal.tapestrylibraryregistry.TapestryLibraryRegistryPackage;
/**
* EMF adapter that attempts to always maintain a default implementation
* JSFLibrary upon addition and removal of JSFLibrary instances and upon
* changing of a JSFLibrary instance's implementation property.
*
* @author Ian Trimble - Oracle
* @deprecated
*/
public class MaintainDefaultImplementationAdapter extends AdapterImpl {
private static MaintainDefaultImplementationAdapter INSTANCE =
new MaintainDefaultImplementationAdapter();
/**
* Gets the single instance of this adapter.
*
* @return The single instance of this adapter.
*/
public static MaintainDefaultImplementationAdapter getInstance() {
return INSTANCE;
}
/**
* Called to notify this adapter that a change has occured.
*
* @param notification EMF Notification instance
*/
public void notifyChanged(Notification notification) {
Object objNotifier = notification.getNotifier();
if (objNotifier instanceof TapestryLibraryRegistry) {
int eventType = notification.getEventType();
switch (eventType) {
case Notification.ADD:
Object objNewValue = notification.getNewValue();
if (objNewValue instanceof TapestryLibrary) {
libraryAdded((TapestryLibrary)objNewValue);
}
break;
case Notification.REMOVE:
Object objOldValue = notification.getOldValue();
if (objOldValue instanceof TapestryLibrary) {
libraryRemoved((TapestryLibrary)objOldValue);
}
break;
}
} else if (objNotifier instanceof TapestryLibrary) {
if (notification.getFeatureID(TapestryLibrary.class) == TapestryLibraryRegistryPackage.JSF_LIBRARY__IMPLEMENTATION) {
implementationFlagSet((TapestryLibrary)objNotifier);
}
}
}
/**
* Checks if the library added is an implementation and, if so, makes it
* the default implementation if it is the only implementation.
*
* @param library JSFLibrary instance
*/
protected void libraryAdded(TapestryLibrary library) {
if (library != null && library.isImplementation()) {
TapestryLibraryRegistry jsfLibReg = TapestryLibraryRegistryUtil.getInstance().getTapestryLibraryRegistry();
EList impls = jsfLibReg.getImplTapestryLibraries();
if (impls.size() == 1) {
jsfLibReg.setDefaultImplementation(library);
}
}
}
/**
* Checks if the library removed is the default implementation and, if so,
* makes the first remaining implementation the new default or nulls out
* the default implementation if no other implementation remains.
*
* @param library JSFLibrary instance
*/
protected void libraryRemoved(TapestryLibrary library) {
if (library != null && library.isImplementation()) {
TapestryLibraryRegistry jsfLibReg = TapestryLibraryRegistryUtil.getInstance().getTapestryLibraryRegistry();
TapestryLibrary defaultImpl = jsfLibReg.getDefaultImplementation();
if (defaultImpl == null || library.getID().equals(defaultImpl.getID())) {
setNewDefaultImplementation();
}
}
}
/**
* Checks if the implementation flag of the JSFLibrary has been changed
* such that it is now eligible to become the default implementation or
* such that it is no longer eligible as the default implementation and
* sets the default implementation appropriately. Note that the passed
* JSFLibrary instance must have been added to the model before calling
* this method for it to have any effect.
*
* @param library JSFLibrary instance
*/
private void implementationFlagSet(TapestryLibrary library) {
TapestryLibraryRegistry jsfLibReg = TapestryLibraryRegistryUtil.getInstance().getTapestryLibraryRegistry();
if (jsfLibReg != null) {
TapestryLibrary defaultImpl = jsfLibReg.getDefaultImplementation();
if (
library.isImplementation() &&
defaultImpl == null
) {
jsfLibReg.setDefaultImplementation(library);
} else if (
!library.isImplementation() &&
(defaultImpl != null && library.getID().equals(defaultImpl.getID())))
{
setNewDefaultImplementation();
}
}
}
/**
* Sets the first available JSFLibrary marked as an implementation as the
* default implementation or sets the default implementation to null if no
* JSFLibrary is marked as an implementation.
*/
protected void setNewDefaultImplementation() {
TapestryLibraryRegistry jsfLibReg = TapestryLibraryRegistryUtil.getInstance().getTapestryLibraryRegistry();
EList impls = jsfLibReg.getImplTapestryLibraries();
if (impls.size() > 0) {
jsfLibReg.setDefaultImplementation((TapestryLibrary)impls.get(0));
} else {
jsfLibReg.setDefaultImplementation(null);
}
}
}