AbstractModelManager.java

/*=============================================================================#
 # Copyright (c) 2009-2016 Stephan Wahlbrink (WalWare.de) 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:
 #     Stephan Wahlbrink - initial API and implementation
 #=============================================================================*/

package de.walware.ecommons.ltk.core.impl;

import java.util.List;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.jobs.Job;

import de.walware.ecommons.FastList;

import de.walware.ecommons.ltk.IElementChangedListener;
import de.walware.ecommons.ltk.IModelManager;
import de.walware.ecommons.ltk.LTK;
import de.walware.ecommons.ltk.WorkingContext;
import de.walware.ecommons.ltk.core.model.ISourceUnit;


public abstract class AbstractModelManager implements IModelManager {
	
	
	protected static class ContextItem {
		
		public final WorkingContext context;
		
		public final FastList<IElementChangedListener> listeners= new FastList<>(IElementChangedListener.class);
		
		
		protected ContextItem(final WorkingContext context) {
			this.context= context;
		}
		
		
		@Override
		public final int hashCode() {
			return this.context.hashCode();
		}
		
		@Override
		public final boolean equals(final Object obj) {
			return (this == obj);
		}
		
	}
	
	private static final IElementChangedListener[] NO_LISTENERS= new IElementChangedListener[0];
	
	private class RefreshJob extends Job {
		
		
		private final List<ISourceUnit> list;
		
		private final int flags;
		
		
		public RefreshJob(final WorkingContext context, final int flags) {
			super("Model Refresh"); //$NON-NLS-1$
			setUser(false);
			setSystem(true);
			setPriority(DECORATE);
			
			this.list= LTK.getSourceUnitManager().getOpenSourceUnits(AbstractModelManager.this.typeId, context);
			this.flags= flags;
		}
		
		@Override
		protected IStatus run(final IProgressMonitor monitor) {
			for (final ISourceUnit su : this.list) {
				su.getModelInfo(null, this.flags, monitor);
			}
			return Status.OK_STATUS;
		}
		
	}
	
	
	private final String typeId;
	
	private final FastList<ContextItem> contexts= new FastList<>(ContextItem.class, FastList.IDENTITY);
	
	
	public AbstractModelManager(final String typeId) {
		this.typeId= typeId;
	}
	
	
	public String getModelTypeId() {
		return this.typeId;
	}
	
	protected ContextItem getContextItem(final WorkingContext context, final boolean create) {
		while (true) {
			final ContextItem[] contextItems= this.contexts.toArray();
			for (int i= 0; i < contextItems.length; i++) {
				if (contextItems[i].context == context) {
					return contextItems[i];
				}
			}
			if (!create) {
				return null;
			}
			synchronized (this.contexts) {
				if (contextItems == this.contexts.toArray()) {
					final ContextItem item= doCreateContextItem(context);
					this.contexts.add(item);
					return item;
				}
			}
		}
	}
	
	protected ContextItem doCreateContextItem(final WorkingContext context) {
		return new ContextItem(context);
	}
	
	@Override
	public void addElementChangedListener(final IElementChangedListener listener,
			final WorkingContext context) {
		final ContextItem contextItem= getContextItem(context, true);
		contextItem.listeners.add(listener);
	}
	
	@Override
	public void removeElementChangedListener(final IElementChangedListener listener,
			final WorkingContext context) {
		final ContextItem contextItem= getContextItem(context, false);
		if (contextItem != null) {
			contextItem.listeners.remove(listener);
		}
	}
	
	protected IElementChangedListener[] getElementChangedListeners(final WorkingContext context) {
		final ContextItem contextItem= getContextItem(context, false);
		if (contextItem == null) {
			return NO_LISTENERS;
		}
		return contextItem.listeners.toArray();
	}
	
	/**
	 * Refresh reuses existing ast
	 */
	@Override
	public void refresh(final WorkingContext context) {
		new RefreshJob(context, (MODEL_DEPENDENCIES | RECONCILE)).schedule();
	}
	
	@Override
	public void registerDependentUnit(final ISourceUnit su) {
	}
	
	@Override
	public void deregisterDependentUnit(final ISourceUnit su) {
	}
	
}