| /******************************************************************************* |
| * Copyright (c) 2006, 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.equinox.internal.p2.director; |
| |
| import org.eclipse.core.runtime.IProgressMonitor; |
| import org.eclipse.core.runtime.ProgressMonitorWrapper; |
| |
| /** |
| * This class provides a simulation of progress. This is useful |
| * for situations where computing the amount of work to do in advance |
| * is too costly. The monitor will accept any number of calls to |
| * {@link #worked(int)}, and will scale the actual reported work appropriately |
| * so that the progress never quite completes. |
| */ |
| class InfiniteProgress extends ProgressMonitorWrapper { |
| /* |
| * Fields for progress monitoring algorithm. |
| * Initially, give progress for every 4 resources, double |
| * this value at halfway point, then reset halfway point |
| * to be half of remaining work. (this gives an infinite |
| * series that converges at total work after an infinite |
| * number of resources). |
| */ |
| private int totalWork; |
| private int currentIncrement = 4; |
| private int halfWay; |
| private int nextProgress = currentIncrement; |
| private int worked = 0; |
| |
| protected InfiniteProgress(IProgressMonitor monitor) { |
| super(monitor); |
| } |
| |
| public void beginTask(String name, int work) { |
| super.beginTask(name, work); |
| this.totalWork = work; |
| this.halfWay = totalWork / 2; |
| } |
| |
| public void worked(int work) { |
| if (--nextProgress <= 0) { |
| //we have exhausted the current increment, so report progress |
| super.worked(1); |
| worked++; |
| if (worked >= halfWay) { |
| //we have passed the current halfway point, so double the |
| //increment and reset the halfway point. |
| currentIncrement *= 2; |
| halfWay += (totalWork - halfWay) / 2; |
| } |
| //reset the progress counter to another full increment |
| nextProgress = currentIncrement; |
| } |
| } |
| |
| } |