/*******************************************************************************
* Copyright (c) 2005, 2016 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.dltk.core;
import org.eclipse.core.resources.IProject;
/**
* Selects a contributed extension implementation based upon the <code>id</code>
* it was registered with when the plugin containing its extension definition
* was loaded.
*
* <p>
* If a saved contribution id can not be found, the implementation will fall
* back to selecting based upon priority.
* </p>
*/
public abstract class DLTKIdContributionSelector extends
DLTKPriorityContributionSelector {
/**
* Selects the contribution implementation currently in use as defined by
* the user's preferences.
*
* @param contributions
* list of contribution implementations
*
* @return currently selected implementation
*/
@Override
public IDLTKContributedExtension select(
IDLTKContributedExtension[] contributions, IProject project) {
PreferencesLookupDelegate delegate = new PreferencesLookupDelegate(
project);
String id = getSavedContributionId(delegate);
if (id != null) {
for (int i = 0; i < contributions.length; i++) {
IDLTKContributedExtension contrib = contributions[i];
if (contrib.getId().equals(id)) {
return contrib;
}
}
}
/*
* if a contribution was not found that matched the saved contribution
* id, pick one based upon its priority
*/
return super.select(contributions, project);
}
/**
* Returns the id of the currently selected contribution.
*
* <p>
* Sub-classes should use the preference lookup delegate to retrieve the
* saved value.
* </p>
*/
protected abstract String getSavedContributionId(
PreferencesLookupDelegate delegate);
}