/*******************************************************************************
* Copyright (c) 2012, 2015 Obeo.
* 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:
* Obeo - initial API and implementation
*******************************************************************************/
package org.eclipse.emf.compare.rcp.ui.internal.contentmergeviewer.accessor.impl;
import com.google.common.collect.ImmutableList;
import org.eclipse.emf.common.notify.AdapterFactory;
import org.eclipse.emf.compare.Diff;
import org.eclipse.emf.compare.rcp.ui.internal.mergeviewer.item.impl.MergeViewerItem;
import org.eclipse.emf.compare.rcp.ui.mergeviewer.IMergeViewer.MergeViewerSide;
import org.eclipse.emf.compare.rcp.ui.mergeviewer.item.IMergeViewerItem;
import org.eclipse.emf.compare.utils.ReferenceUtil;
import org.eclipse.emf.ecore.EObject;
/**
* A specific {@link AbstractStructuralFeatureAccessor} for mono-valued structural feature objects.
*
* @author <a href="mailto:mikael.barbero@obeo.fr">Mikael Barbero</a>
* @since 4.0
*/
public class SingleStructuralFeatureAccessorImpl extends AbstractStructuralFeatureAccessor {
/**
* Default constructor.
*
* @param adapterFactory
* the adapater factory used to create the accessor.
* @param diff
* the diff associated with this accessor.
* @param side
* the side of the accessor.
*/
public SingleStructuralFeatureAccessorImpl(AdapterFactory adapterFactory, Diff diff,
MergeViewerSide side) {
super(adapterFactory, diff, side);
}
/**
* {@inheritDoc}
*
* @see org.eclipse.emf.compare.rcp.ui.contentmergeviewer.accessor.ICompareAccessor.#getItems()
*/
public ImmutableList<? extends IMergeViewerItem> getItems() {
Object thisSideValue = getValue(getSide());
if (thisSideValue == null && getSide() == MergeViewerSide.ANCESTOR) {
// No use retrieving all sides ...
return ImmutableList.of();
}
Object leftValue = getValue(MergeViewerSide.LEFT);
Object rightValue = getValue(MergeViewerSide.RIGHT);
Object ancestorValue = getValue(MergeViewerSide.ANCESTOR);
// there can be only one diff on !many structural feature.
Diff diff = getInitialDiff();
IMergeViewerItem insertionPoint = new MergeViewerItem(getComparison(), diff, leftValue, rightValue,
ancestorValue, getSide(), getRootAdapterFactory());
return ImmutableList.of(insertionPoint);
}
/**
* Get the value associated to the given side.
*
* @param side
* the given side.
* @return the value associated to the given side.
*/
private Object getValue(MergeViewerSide side) {
Object value = null;
EObject eObject = getEObject(side);
if (eObject != null) {
value = ReferenceUtil.safeEGet(eObject, getStructuralFeature());
}
return value;
}
}