| /******************************************************************************* |
| * Copyright (c) 2002 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v0.5 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v05.html |
| * |
| * Contributors: |
| * IBM - Initial implementation |
| ******************************************************************************/ |
| package org.eclipse.team.internal.core.streams; |
| |
| import java.io.FilterInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InterruptedIOException; |
| |
| import org.eclipse.core.runtime.IProgressMonitor; |
| import org.eclipse.core.runtime.OperationCanceledException; |
| |
| /** |
| * Updates a progress monitor as bytes are read from the input stream. |
| * Also starts a background thread to provide responsive cancellation on read(). |
| * |
| * Supports resuming partially completed operations after an InterruptedIOException |
| * if the underlying stream does. Check the bytesTransferred field to determine how |
| * much of the operation completed; conversely, at what point to resume. |
| */ |
| public abstract class ProgressMonitorInputStream extends FilterInputStream { |
| private IProgressMonitor monitor; |
| private int updateIncrement; |
| private long bytesTotal; |
| private long bytesRead = 0; |
| private long lastUpdate = -1; |
| private long nextUpdate = 0; |
| |
| /** |
| * Creates a progress monitoring input stream. |
| * @param in the underlying input stream |
| * @param bytesTotal the number of bytes to read in total (passed to updateMonitor()) |
| * @param updateIncrement the number of bytes read between updates |
| * @param monitor the progress monitor |
| */ |
| public ProgressMonitorInputStream(InputStream in, long bytesTotal, int updateIncrement, IProgressMonitor monitor) { |
| super(in); |
| this.bytesTotal = bytesTotal; |
| this.updateIncrement = updateIncrement; |
| this.monitor = monitor; |
| update(true); |
| } |
| |
| protected abstract void updateMonitor(long bytesRead, long size, IProgressMonitor monitor); |
| |
| /** |
| * Wraps the underlying stream's method. |
| * Updates the progress monitor to the final number of bytes read. |
| * @throws IOException if an i/o error occurs |
| */ |
| public void close() throws IOException { |
| try { |
| in.close(); |
| } finally { |
| update(true); |
| } |
| } |
| |
| /** |
| * Wraps the underlying stream's method. |
| * Updates the progress monitor if the next update increment has been reached. |
| * @throws InterruptedIOException if the operation was interrupted before all of the |
| * bytes specified have been skipped, bytesTransferred will be zero |
| * @throws IOException if an i/o error occurs |
| */ |
| public int read() throws IOException { |
| int b = in.read(); |
| if (b != -1) { |
| bytesRead += 1; |
| update(false); |
| } |
| return b; |
| } |
| |
| /** |
| * Wraps the underlying stream's method. |
| * Updates the progress monitor if the next update increment has been reached. |
| * @throws InterruptedIOException if the operation was interrupted before all of the |
| * bytes specified have been skipped, bytesTransferred may be non-zero |
| * @throws IOException if an i/o error occurs |
| */ |
| public int read(byte[] buffer, int offset, int length) throws IOException { |
| try { |
| int count = in.read(buffer, offset, length); |
| if (count != -1) { |
| bytesRead += count; |
| update(false); |
| } |
| return count; |
| } catch (InterruptedIOException e) { |
| bytesRead += e.bytesTransferred; |
| update(false); |
| throw e; |
| } |
| } |
| |
| /** |
| * Wraps the underlying stream's method. |
| * Updates the progress monitor if the next update increment has been reached. |
| * @throws InterruptedIOException if the operation was interrupted before all of the |
| * bytes specified have been skipped, bytesTransferred may be non-zero |
| * @throws IOException if an i/o error occurs |
| */ |
| public long skip(long amount) throws IOException { |
| try { |
| long count = in.skip(amount); |
| bytesRead += count; |
| update(false); |
| return count; |
| } catch (InterruptedIOException e) { |
| bytesRead += e.bytesTransferred; |
| update(false); |
| throw e; |
| } |
| } |
| |
| /** |
| * Mark is not supported by the wrapper even if the underlying stream does, returns false. |
| */ |
| public boolean markSupported() { |
| return false; |
| } |
| |
| private void update(boolean now) { |
| if (bytesRead >= nextUpdate || now) { |
| nextUpdate = bytesRead - (bytesRead % updateIncrement); |
| if (nextUpdate != lastUpdate) updateMonitor(nextUpdate, bytesTotal, monitor); |
| lastUpdate = nextUpdate; |
| nextUpdate += updateIncrement; |
| } |
| } |
| } |