Copyright (c) 2010, 2013 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2010, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.debug.internal.core;

import org.eclipse.core.runtime.preferences.IEclipsePreferences;
import org.eclipse.core.runtime.preferences.IPreferenceNodeVisitor;
import org.eclipse.core.runtime.preferences.PreferenceModifyListener;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.debug.core.ILaunchConfigurationType;
import org.osgi.service.prefs.BackingStoreException;

Used to listen for preference imports that include changes to preferred
launch delegates.
Since:
3.6 TODO can we roll this into general preference listening?/**
 * Used to listen for preference imports that include changes to preferred
 * launch delegates.
 *
 * @since 3.6 TODO can we roll this into general preference listening?
 */
public class PreferredDelegateModifyListener extends PreferenceModifyListener {
	class Visitor implements IPreferenceNodeVisitor {

		@Override
		public boolean visit(IEclipsePreferences node) throws BackingStoreException {
			if (node.name().equals(DebugPlugin.getUniqueIdentifier())) {
				// reset preferred delegates, so they are re-initialized from the preferences
				LaunchManager manager = (LaunchManager)DebugPlugin.getDefault().getLaunchManager();
				manager.resetPreferredDelegates();
				ILaunchConfigurationType[] types = manager.getLaunchConfigurationTypes();
				for (ILaunchConfigurationType type : types) {
					((LaunchConfigurationType) type).resetPreferredDelegates();
				}
				return false;
			}
			return true;
		}

	}

	@Override
	public IEclipsePreferences preApply(IEclipsePreferences node) {
		try {
			// force VMs to be initialized before we import the new VMs
			node.accept(new Visitor());
		} catch (BackingStoreException e) {
			DebugPlugin.log(e);
		}
		return node;
	}

}