org.eclipse.gmf.runtime.diagram.ui/src/org/eclipse/gmf/runtime/diagram/ui/view/factories/ConnectionViewFactory.java

/******************************************************************************
 * Copyright (c) 2005, 2009 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 Corporation - initial API and implementation 
 ****************************************************************************/


package org.eclipse.gmf.runtime.diagram.ui.view.factories;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Status;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.transaction.Transaction;
import org.eclipse.emf.transaction.TransactionalEditingDomain;
import org.eclipse.emf.transaction.impl.InternalTransaction;
import org.eclipse.emf.transaction.impl.InternalTransactionalEditingDomain;
import org.eclipse.emf.workspace.AbstractEMFOperation;
import org.eclipse.gmf.runtime.common.core.util.Log;
import org.eclipse.gmf.runtime.common.core.util.StringStatics;
import org.eclipse.gmf.runtime.common.core.util.Trace;
import org.eclipse.gmf.runtime.diagram.core.preferences.PreferencesHint;
import org.eclipse.gmf.runtime.diagram.core.util.ViewUtil;
import org.eclipse.gmf.runtime.diagram.core.view.factories.ViewFactory;
import org.eclipse.gmf.runtime.diagram.ui.internal.DiagramUIDebugOptions;
import org.eclipse.gmf.runtime.diagram.ui.internal.DiagramUIPlugin;
import org.eclipse.gmf.runtime.diagram.ui.internal.DiagramUIStatusCodes;
import org.eclipse.gmf.runtime.diagram.ui.preferences.IPreferenceConstants;
import org.eclipse.gmf.runtime.notation.Bendpoints;
import org.eclipse.gmf.runtime.notation.Edge;
import org.eclipse.gmf.runtime.notation.NotationFactory;
import org.eclipse.gmf.runtime.notation.NotationPackage;
import org.eclipse.gmf.runtime.notation.RelativeBendpoints;
import org.eclipse.gmf.runtime.notation.Routing;
import org.eclipse.gmf.runtime.notation.RoutingStyle;
import org.eclipse.gmf.runtime.notation.View;
import org.eclipse.gmf.runtime.notation.datatype.RelativeBendpoint;
import org.eclipse.jface.preference.IPreferenceStore;

/**
 * This is the bas factory class for all connection views, it will 
 * create the view and decorate it using the default decorations
 * you can subclass it to add more decorations, or customize the 
 * way it looks, like adding new style
 * @see #createView(IAdaptable, View, String, int, boolean, String)
 * @see #decorateView(View, View, IAdaptable, String, int, boolean)
 * @see #createStyles()
 * @author mmostafa
 * 
 */

public class ConnectionViewFactory
	extends AbstractViewFactory implements ViewFactory {
	private static final Map options = new HashMap();	
    static {
        options.put(Transaction.OPTION_UNPROTECTED, Boolean.TRUE);
        options.put(Transaction.OPTION_NO_NOTIFICATIONS, Boolean.TRUE);
        options.put(Transaction.OPTION_NO_TRIGGERS, Boolean.TRUE);
    }
	
	/* (non-Javadoc)
	 * @see org.eclipse.gmf.runtime.diagram.core.view.factories.ViewFactory#createView(org.eclipse.core.runtime.IAdaptable, org.eclipse.gmf.runtime.notation.View, java.lang.String, int, boolean, java.lang.String)
	 */
	public View createView(final IAdaptable semanticAdapter,
			final View containerView, final String semanticHint,
			final int index, final boolean persisted,
			final PreferencesHint preferencesHint) {

		setPreferencesHint(preferencesHint);

		final Edge edge = createEdge();
		List styles = createStyles(edge);
        if (styles.size() > 0) {
        	edge.getStyles().addAll(styles);
        }
        
        Bendpoints bendPoints = createBendpoints();
        if (bendPoints != null) {
			edge.setBendpoints(bendPoints);
		}

		edge.setType(semanticHint);
		
		// decorate view assumes the view had been inserted already, so 
		// we had to call insert child before calling decorate view
		ViewUtil.insertChildView(containerView,edge, index, persisted);
        
        EObject semanticEl = semanticAdapter==null ? null : (EObject)semanticAdapter.getAdapter(EObject.class);
        if (semanticEl==null)
            // enforce a set to NULL
            edge.setElement(null);
        else if (requiresElement(semanticAdapter,containerView)){
            edge.setElement(semanticEl);
        }
        
        TransactionalEditingDomain domain = getEditingDomain(semanticEl, containerView);
		
        if (isUnProtectedSilentTransactionInProgress(domain)){
            // decorate view had to run as a silent operation other wise
            // it will generate too many events
            decorateView(containerView, edge, semanticAdapter,
                semanticHint, index, true);
            
        }else{
    		AbstractEMFOperation operation = new AbstractEMFOperation(
                domain, StringStatics.BLANK,
    			options) {
    
    			protected IStatus doExecute(IProgressMonitor monitor,
    					IAdaptable info)
    				throws ExecutionException {
    			    decorateView(containerView, edge, semanticAdapter,
    					semanticHint, index, true);
    
    				return Status.OK_STATUS;
    			}
    		};
    		try {
    			operation.setReuseParentTransaction(true);
    			operation.execute(new NullProgressMonitor(), null);
    		} catch (ExecutionException e) {
    			Trace.catching(DiagramUIPlugin.getInstance(),
    				DiagramUIDebugOptions.EXCEPTIONS_CATCHING, getClass(),
    				"createView", e); //$NON-NLS-1$
    			Log
    				.warning(DiagramUIPlugin.getInstance(),
    					DiagramUIStatusCodes.IGNORED_EXCEPTION_WARNING,
    					"createView", e); //$NON-NLS-1$
    		}
        }

		return edge;
	}
	
	/**
	 * Creates a blank notation model element for edge.
	 * 
	 * @return the new edge
	 * @since 1.2
	 */
	protected Edge createEdge() {
		return NotationFactory.eINSTANCE.createEdge();
	}
	
	/**
	 * this method will create the default bend point on the connection, connections are
	 * created as Straight linem you can override this method in your own factory that 
	 * subclass this class and change this behavior by adding extra bend points or returning
	 * a new list of bend points. This method get called by @link #createView(IAdaptable, View, String, int, boolean) 
	 * @return a list of style for the newly created view or an empty list if none (do not return null)
	 */
	protected Bendpoints createBendpoints() {
		RelativeBendpoints bendpoints = NotationFactory.eINSTANCE
			.createRelativeBendpoints();
		List points = new ArrayList(2);
		points.add(new RelativeBendpoint());
		points.add(new RelativeBendpoint());
		bendpoints.setPoints(points);
		return bendpoints;
	}

	/**
	 * This method is responsible for decorating the created view, it get called
	 * by the Factory method @link #createView(IAdaptable, View, String, int, boolean),
	 * it will intiliaze the view with the default preferences also it will create 
	 * the default elements of the <code>View</code> if it had any
	 * @param containerView the container of the view
	 * @param view the view itself
	 * @param element the semantic elemnent of the view (it could be null)
	 * @param semanticHint the semantic hint of the view
	 * @param index the index of the view
	 * @param persisted flag indicating the the view was created as persisted or not
	 */
	protected void decorateView(View containerView, View view, IAdaptable element,
			String semanticHint, int index, boolean persisted) {
		initializeFromPreferences(view);
	}
	

	/**
	 * this method is called by @link #createView(IAdaptable, View, String, int, boolean) to 
	 * create the styles for the view that will be created, you can override this 
	 * method in you factory sub class to provide additional styles
	 * @return a list of style for the newly created view or an empty list if none (do not return null)
	 */
	protected List createStyles(View view) {
		List styles = new ArrayList();
		styles.add(NotationFactory.eINSTANCE.createConnectorStyle());
		return styles;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.gmf.runtime.diagram.ui.internal.view.factories.AbstractViewFactory#initializeFromPreferences(org.eclipse.gmf.runtime.notation.View)
	 */
	protected void initializeFromPreferences(View view) {
		super.initializeFromPreferences(view);

		IPreferenceStore store = (IPreferenceStore) getPreferencesHint()
			.getPreferenceStore();

		RoutingStyle routingStyle = (RoutingStyle)view.getStyle(NotationPackage.Literals.ROUTING_STYLE);
		if (routingStyle != null) {
			Routing routing = Routing.get(store
				.getInt(IPreferenceConstants.PREF_LINE_STYLE));
			if (routing != null) {
				routingStyle.setRouting(routing);
			}
		}				
	}
    
    /**
     * Checks if the current active transaction is a unprotected amd silent
     * 
     * @param domain , the domain to use during the check
     * @return <code>true</code> if the current active transaction is unprotected and silent 
     */
    protected static boolean isUnProtectedSilentTransactionInProgress(TransactionalEditingDomain domain) {
        if (domain instanceof InternalTransactionalEditingDomain){
            InternalTransactionalEditingDomain internalEditingDomain = 
                (InternalTransactionalEditingDomain)domain;
            InternalTransaction transaction = internalEditingDomain.getActiveTransaction();
            if (transaction!=null && !transaction.isReadOnly()) {
                Object unprotectedMode = transaction.getOptions().get(Transaction.OPTION_UNPROTECTED); 
                if (Boolean.TRUE.equals(unprotectedMode)) {
                    // check for silent
                    Object noNotificationMode = transaction.getOptions().get(Transaction.OPTION_NO_NOTIFICATIONS);
                    Object noTriggersMode = transaction.getOptions().get(Transaction.OPTION_NO_TRIGGERS);
                    if (Boolean.TRUE.equals(noNotificationMode) &&
                        Boolean.TRUE.equals(noTriggersMode)) {
                        return true;
                    }
                }
            }
        }
        return false;
    }

}