/*******************************************************************************
* Copyright (c) 2006, 2012 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;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.RejectedExecutionException;
import org.eclipse.cdt.dsf.concurrent.CountingRequestMonitor;
import org.eclipse.cdt.dsf.concurrent.DsfRunnable;
import org.eclipse.cdt.dsf.concurrent.IDsfStatusConstants;
import org.eclipse.cdt.dsf.concurrent.ImmediateExecutor;
import org.eclipse.cdt.dsf.concurrent.RequestMonitor;
import org.eclipse.cdt.dsf.concurrent.ThreadSafe;
import org.eclipse.cdt.dsf.internal.ui.DsfUIPlugin;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IChildrenCountUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IChildrenUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IColumnPresentation;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IHasChildrenUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IModelProxy;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IPresentationContext;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IViewerInputUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IViewerUpdate;
/**
* Base implementation for View Model Adapters. The implementation uses
* its own single-thread executor for communicating with providers and
* layout nodes.
*
* @since 1.0
*/
@ThreadSafe
abstract public class AbstractVMAdapter implements IVMAdapter
{
private boolean fDisposed;
private final Map<IPresentationContext, IVMProvider> fViewModelProviders =
Collections.synchronizedMap( new HashMap<IPresentationContext, IVMProvider>() );
/**
* 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 AbstractVMAdapter() {
}
@Override
@ThreadSafe
public IVMProvider getVMProvider(IPresentationContext context) {
synchronized(fViewModelProviders) {
if (fDisposed) return null;
IVMProvider provider = fViewModelProviders.get(context);
if (provider == null) {
provider = createViewModelProvider(context);
if (provider != null) {
fViewModelProviders.put(context, provider);
}
}
return provider;
}
}
/**
* {@inheritDoc}
*
* @since 1.1
*/
@Override
public IVMProvider[] getActiveProviders() {
synchronized(fViewModelProviders) {
return fViewModelProviders.values().toArray(new IVMProvider[fViewModelProviders.size()]);
}
}
public void dispose() {
IVMProvider[] providers = new IVMProvider[0];
synchronized(fViewModelProviders) {
providers = fViewModelProviders.values().toArray(new IVMProvider[fViewModelProviders.size()]);
fViewModelProviders.clear();
fDisposed = true;
}
for (final IVMProvider provider : providers) {
try {
provider.getExecutor().execute(new Runnable() {
@Override
public void run() {
provider.dispose();
}
});
} catch (RejectedExecutionException e) {
// Not much we can do at this point.
}
}
}
/**
* @return whether this VM adapter is disposed.
*
* @since 1.1
*/
public boolean isDisposed() {
return fDisposed;
}
@Override
public void update(IHasChildrenUpdate[] updates) {
handleUpdate(updates);
}
@Override
public void update(IChildrenCountUpdate[] updates) {
handleUpdate(updates);
}
@Override
public void update(final IChildrenUpdate[] updates) {
handleUpdate(updates);
}
private void handleUpdate(IViewerUpdate[] updates) {
IVMProvider provider = getVMProvider(updates[0].getPresentationContext());
if (provider != null) {
updateProvider(provider, updates);
} else {
for (IViewerUpdate update : updates) {
update.setStatus(new Status(IStatus.ERROR, DsfUIPlugin.PLUGIN_ID, IDsfStatusConstants.INTERNAL_ERROR,
"No model provider for update " + update, null)); //$NON-NLS-1$
update.done();
}
}
}
private void updateProvider(final IVMProvider provider, final IViewerUpdate[] updates) {
try {
provider.getExecutor().execute(new Runnable() {
@Override
public void run() {
if (updates instanceof IHasChildrenUpdate[]) {
provider.update((IHasChildrenUpdate[])updates);
} else if (updates instanceof IChildrenCountUpdate[]) {
provider.update((IChildrenCountUpdate[])updates);
} else if (updates instanceof IChildrenUpdate[]) {
provider.update((IChildrenUpdate[])updates);
}
}
});
} catch (RejectedExecutionException e) {
for (IViewerUpdate update : updates) {
update.setStatus(new Status(IStatus.ERROR, DsfUIPlugin.PLUGIN_ID, IDsfStatusConstants.INTERNAL_ERROR,
"Display is disposed, cannot complete update " + update, null)); //$NON-NLS-1$
update.done();
}
}
}
@Override
public IModelProxy createModelProxy(Object element, IPresentationContext context) {
IVMProvider provider = getVMProvider(context);
if (provider != null) {
return provider.createModelProxy(element, context);
}
return null;
}
@Override
public IColumnPresentation createColumnPresentation(IPresentationContext context, Object element) {
final IVMProvider provider = getVMProvider(context);
if (provider != null) {
return provider.createColumnPresentation(context, element);
}
return null;
}
@Override
public String getColumnPresentationId(IPresentationContext context, Object element) {
final IVMProvider provider = getVMProvider(context);
if (provider != null) {
return provider.getColumnPresentationId(context, element);
}
return null;
}
@Override
public void update(IViewerInputUpdate update) {
final IVMProvider provider = getVMProvider(update.getPresentationContext());
if (provider != null) {
provider.update(update);
} else {
update.setStatus(new Status(IStatus.ERROR, DsfUIPlugin.PLUGIN_ID, "not supported")); //$NON-NLS-1$
update.done();
}
}
/**
* Creates a new View Model Provider for given presentation context. Returns null
* if the presentation context is not supported.
*/
@ThreadSafe
abstract protected IVMProvider createViewModelProvider(IPresentationContext context);
/**
* Dispatch given event to VM providers interested in events.
*
* @since 1.1
*/
protected final void handleEvent(final Object event) {
final List<IVMEventListener> eventListeners = new ArrayList<IVMEventListener>();
aboutToHandleEvent(event);
for (IVMProvider vmProvider : getActiveProviders()) {
if (vmProvider instanceof IVMEventListener) {
eventListeners.add((IVMEventListener)vmProvider);
}
}
if (!eventListeners.isEmpty()) {
final CountingRequestMonitor crm = new CountingRequestMonitor(ImmediateExecutor.getInstance(), null) {
@Override
protected void handleCompleted() {
if (isDisposed()) {
return;
}
doneHandleEvent(event);
}
};
int count = 0;
for (final IVMEventListener vmEventListener : eventListeners) {
RequestMonitor listenerRm = null;
if (vmEventListener.shouldWaitHandleEventToComplete()) {
listenerRm = crm;
count++;
} else {
// Create a dummy request monitor for the handling of this event.
listenerRm = new RequestMonitor(ImmediateExecutor.getInstance(), null);
}
final RequestMonitor finalListenerRm = listenerRm;
vmEventListener.getExecutor().execute(new DsfRunnable() {
@Override
public void run() {
vmEventListener.handleEvent(event, finalListenerRm);
}});
}
crm.setDoneCount(count);
} else {
doneHandleEvent(event);
}
}
/**
* Given event is about to be handled.
*
* @param event
*
* @since 1.1
*/
protected void aboutToHandleEvent(final Object event) {
}
/**
* Given event has been processed by all VM event listeners.
*
* @param event
*
* @since 1.1
*/
protected void doneHandleEvent(final Object event) {
}
}