/*******************************************************************************
 * Copyright (c) 2000, 2003 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.update.internal.core;


import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.core.runtime.SubProgressMonitor;

public class Policy {
	/**
	 * Progress monitor helpers
	 */
	public static void checkCanceled(IProgressMonitor monitor) {
		if (monitor.isCanceled())
			throw new OperationCanceledException();
	}
	public static IProgressMonitor monitorFor(IProgressMonitor monitor) {
		if (monitor == null)
			return new NullProgressMonitor();
		return monitor;
	}
	
	public static IProgressMonitor subMonitorFor(IProgressMonitor monitor, int ticks) {
		if (monitor == null)
			return new NullProgressMonitor();
		if (monitor instanceof NullProgressMonitor)
			return monitor;
		return new SubProgressMonitor(monitor, ticks);
	}
}