/*******************************************************************************
* Copyright (c) 2006, 2009 Wind River Systems 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:
* Wind River Systems - initial API and implementation
*******************************************************************************/
package org.eclipse.cdt.dsf.ui.viewmodel.datamodel;
import java.util.concurrent.RejectedExecutionException;
import org.eclipse.cdt.dsf.concurrent.ThreadSafe;
import org.eclipse.cdt.dsf.datamodel.IDMEvent;
import org.eclipse.cdt.dsf.service.DsfServiceEventHandler;
import org.eclipse.cdt.dsf.service.DsfSession;
import org.eclipse.cdt.dsf.ui.viewmodel.AbstractVMAdapter;
/**
* Base implementation for DSF-based view model adapters.
*
* @since 1.0
*/
@ThreadSafe
abstract public class AbstractDMVMAdapter extends AbstractVMAdapter
{
private final DsfSession fSession;
/**
* It is theoretically possible for a VM adapter to be disposed before it
* has a chance to register itself as event listener. This flag is used
* to avoid removing itself as listener in such situation.
*/
private boolean fRegisteredAsEventListener = false;
/**
* Constructor for the View Model session. It is tempting to have the
* adapter register itself here with the session as the model adapter, but
* that would mean that the adapter might get accessed on another thread
* even before the deriving class is fully constructed. So it it better
* to have the owner of this object register it with the session.
* @param session
*/
public AbstractDMVMAdapter(DsfSession session) {
super();
fSession = session;
// Add ourselves as listener for DM events events.
try {
session.getExecutor().execute(new Runnable() {
public void run() {
if (DsfSession.isSessionActive(getSession().getId())) {
getSession().addServiceEventListener(AbstractDMVMAdapter.this, null);
fRegisteredAsEventListener = true;
}
}
});
} catch (RejectedExecutionException e) {
// Session shut down, not much we can do but wait to be disposed.
}
}
@Override
public void dispose() {
try {
getSession().getExecutor().execute(new Runnable() {
public void run() {
if (fRegisteredAsEventListener && getSession().isActive()) {
fSession.removeServiceEventListener(AbstractDMVMAdapter.this);
}
}
});
} catch (RejectedExecutionException e) {
// Session shut down.
}
super.dispose();
}
/**
* Returns the DSF session that this adapter is associated with.
* @return
*/
protected DsfSession getSession() { return fSession; }
/**
* Handle "data model changed" event by generating a delta object for each
* view and passing it to the corresponding view model provider. The view
* model provider is then responsible for filling-in and sending the delta
* to the viewer.
*
* @param event
*
* @since 1.1
*/
@DsfServiceEventHandler
public final void eventDispatched(final IDMEvent<?> event) {
// We're in session's executor thread (session in which the event originated).
if (isDisposed()) return;
handleEvent(event);
}
}