| /******************************************************************************* |
| * Copyright (c) 2007, 2009 compeople AG 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: |
| * compeople AG (Stefan Liebig) - initial API and implementation |
| * IBM Corporation - continuing development |
| *******************************************************************************/ |
| package org.eclipse.equinox.internal.provisional.p2.artifact.repository.processing; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import org.eclipse.core.runtime.*; |
| import org.eclipse.equinox.internal.provisional.p2.artifact.repository.IArtifactDescriptor; |
| import org.eclipse.equinox.internal.provisional.p2.repository.IStateful; |
| |
| /** |
| * ProcessingSteps process the data written to them and pass the resultant data on |
| * to a configured destination stream. Steps may monitor (e.g., count) the data, compute information |
| * about the data (e.g., checksum or hash) or transform the data (e.g., unpack200). |
| */ |
| public abstract class ProcessingStep extends OutputStream implements IStateful { |
| |
| private OutputStream destination; |
| private IProgressMonitor monitor; |
| private IStatus status = Status.OK_STATUS; |
| |
| protected ProcessingStep() { |
| super(); |
| } |
| |
| /** |
| * Initialize this processing step according to the information in the given |
| * descriptor and context. After initialization, this step is ready for linking |
| * with other steps or output streams |
| * @param descriptor description of the step |
| * @param context the context in which the step is being used |
| */ |
| public void initialize(ProcessingStepDescriptor descriptor, IArtifactDescriptor context) { |
| // nothing to do here! |
| } |
| |
| /** |
| * Link this step with the given output stream and configure the step to use the given |
| * progress monitor. After linking the step is ready to have data written to it. |
| * @param destination the stream into which to write the processed data |
| * @param monitor the progress monitor to use for reporting activity |
| */ |
| public void link(OutputStream destination, IProgressMonitor monitor) { |
| this.destination = destination; |
| this.monitor = monitor; |
| } |
| |
| /** |
| * Process the given byte and pass the result on to the configured destination stream |
| * @param b the byte being written |
| */ |
| public void write(int b) throws IOException { |
| // nothing to do here! |
| } |
| |
| /** |
| * Flush any unwritten data from this stream. |
| */ |
| public void flush() throws IOException { |
| super.flush(); |
| if (destination != null) |
| destination.flush(); |
| } |
| |
| /** |
| * Close this stream and, if the configured destination is a ProcessingStep, |
| * close it as well. Typically a chain of steps terminates in a conventional |
| * output stream. Implementors of this method should ensure they set the |
| * status of the step. |
| */ |
| public void close() throws IOException { |
| super.close(); |
| if (destination instanceof ProcessingStep) |
| destination.close(); |
| monitor = null; |
| } |
| |
| public IStatus getStatus() { |
| return status; |
| } |
| |
| public void setStatus(IStatus value) { |
| if (value == null) |
| value = Status.OK_STATUS; |
| if (status != null && status.getSeverity() >= value.getSeverity()) |
| return; |
| status = value; |
| } |
| |
| /** |
| * Get the progress monitor. |
| * @return the progress monitor; may be null |
| */ |
| protected IProgressMonitor getProgressMonitor() { |
| return monitor; |
| } |
| |
| /** |
| * Get the stream to write the processed data into. |
| * |
| * @return output stream for processed data |
| */ |
| protected OutputStream getDestination() { |
| return destination; |
| } |
| |
| /** |
| * Return the status of this step. The status will be <code>null</code> if the |
| * step has not yet executed. If the step has executed the returned status |
| * indicates the success or failure of the step. |
| * @param deep whether or not to aggregate the status of any linked steps |
| * @return the requested status |
| */ |
| public IStatus getStatus(boolean deep) { |
| return ProcessingStepHandler.getStatus(this, deep); |
| } |
| } |