bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/internal/p2/core/helpers/FileUtils.java - equinox/rt.equinox.p2 - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007 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.core.helpers;

 import java.io.*;
 import java.util.*;
 import java.util.zip.*;
 import org.eclipse.core.runtime.*;
 import org.eclipse.osgi.util.NLS;

 public class FileUtils {

 	private static File[] untarFile(File source, File outputDir) throws IOException, TarException {
 		TarFile tarFile = new TarFile(source);
 		List untarredFiles = new ArrayList();
 		for (Enumeration e = tarFile.entries(); e.hasMoreElements();) {
 			TarEntry entry = (TarEntry) e.nextElement();
 			InputStream input = tarFile.getInputStream(entry);
 			try {
 				File outFile = new File(outputDir, entry.getName());
 				untarredFiles.add(outFile);
 				if (entry.getFileType() == TarEntry.DIRECTORY) {
 					outFile.mkdirs();
 				} else {
 					if (outFile.exists())
 						outFile.delete();
 					else
 						outFile.getParentFile().mkdirs();
 					try {
 						copyStream(input, false, new FileOutputStream(outFile), true);
 					} catch (FileNotFoundException e1) {
 						// TEMP: ignore this for now in case we're trying to replace
 						// a running eclipse.exe
 					}
 					outFile.setLastModified(entry.getTime());
 				}
 			} finally {
 				input.close();
 			}
 		}
 		return (File[]) untarredFiles.toArray(new File[untarredFiles.size()]);
 	}

 	/**
 	 * Unzip from a File to an output directory.
 	 */
 	public static File[] unzipFile(File zipFile, File outputDir) throws IOException {
 		// check to see if we have a tar'd and gz'd file
 		if (zipFile.getName().toLowerCase().endsWith(".tar.gz")) { //$NON-NLS-1$
 			try {
 				return untarFile(zipFile, outputDir);
 			} catch (TarException e) {
 				throw new IOException(e.getMessage());
 			}
 		}
 		InputStream in = new FileInputStream(zipFile);
 		try {
 			return unzipStream(in, zipFile.length(), outputDir, null, null);
 		} catch (IOException e) {
 			// add the file name to the message
 			throw new IOException(NLS.bind(Messages.Util_Error_Unzipping, zipFile, e.getMessage()));
 		} finally {
 			in.close();
 		}
 	}

 	/**
 	 * Unzip from a File to an output directory, with progress indication.
 	 * monitor may be null.
 	 */
 	public static File[] unzipFile(File zipFile, File outputDir, String taskName, IProgressMonitor monitor) throws IOException {
 		InputStream in = new FileInputStream(zipFile);
 		try {
 			return unzipStream(in, zipFile.length(), outputDir, taskName, monitor);
 		} catch (IOException e) {
 			// add the file name to the message
 			throw new IOException(NLS.bind(Messages.Util_Error_Unzipping, zipFile, e.getMessage()));
 		} finally {
 			in.close();
 		}
 	}

 	/**
 	 * Unzip from an InputStream to an output directory.
 	 */
 	public static File[] unzipStream(InputStream stream, long size, File outputDir, String taskName, IProgressMonitor monitor) throws IOException {
 		InputStream is = monitor == null ? stream : stream; // new ProgressMonitorInputStream(stream, size, size, taskName, monitor); TODO Commented code
 		ZipInputStream in = new ZipInputStream(new BufferedInputStream(is));
 		ZipEntry ze = in.getNextEntry();
 		if (ze == null) {
 			// There must be at least one entry in a zip file.
 			// When there isn't getNextEntry returns null.
 			in.close();
 			throw new IOException(Messages.Util_Invalid_Zip_File_Format);
 		}
 		ArrayList unzippedFiles = new ArrayList();
 		do {
 			File outFile = new File(outputDir, ze.getName());
 			unzippedFiles.add(outFile);
 			if (ze.isDirectory()) {
 				outFile.mkdirs();
 			} else {
 				if (outFile.exists()) {
 					outFile.delete();
 				} else {
 					outFile.getParentFile().mkdirs();
 				}
 				try {
 					copyStream(in, false, new FileOutputStream(outFile), true);
 				} catch (FileNotFoundException e) {
 					// TEMP: ignore this for now in case we're trying to replace
 					// a running eclipse.exe
 				}
 				outFile.setLastModified(ze.getTime());
 			}
 			in.closeEntry();
 		} while ((ze = in.getNextEntry()) != null);
 		in.close();

 		return (File[]) unzippedFiles.toArray(new File[unzippedFiles.size()]);
 	}

 	// Delete empty directories under dir, including dir itself.
 	public static void deleteEmptyDirs(File dir) throws IOException {
 		File[] files = dir.listFiles();
 		if (files != null) {
 			for (int i = 0; i < files.length; i += 1) {
 				deleteEmptyDirs(files[i]);
 			}
 			dir.getCanonicalFile().delete();
 		}
 	}

 	// Delete the given file whether it is a file or a directory
 	public static void deleteAll(File file) {
 		if (!file.exists())
 			return;
 		if (file.isDirectory()) {
 			File[] files = file.listFiles();
 			if (files != null)
 				for (int i = 0; i < files.length; i++)
 					deleteAll(files[i]);
 		}
 		file.delete();
 	}

 	/**
 	 * Copy an input stream to an output stream.
 	 * Optionally close the streams when done.
 	 * Return the number of bytes written.
 	 */
 	public static int copyStream(InputStream in, boolean closeIn, OutputStream out, boolean closeOut) throws IOException {
 		try {
 			int written = 0;
 			byte[] buffer = new byte[16 * 1024];
 			int len;
 			while ((len = in.read(buffer)) != -1) {
 				out.write(buffer, 0, len);
 				written += len;
 			}
 			return written;
 		} finally {
 			try {
 				if (closeIn) {
 					in.close();
 				}
 			} finally {
 				if (closeOut) {
 					out.close();
 				}
 			}
 		}
 	}

 	public static void copy(File source, File destination, File root, boolean overwrite) throws IOException {
 		File sourceFile = new File(source, root.getPath());
 		if (!sourceFile.exists())
 			throw new FileNotFoundException("Source: " + sourceFile + " does not exist"); //$NON-NLS-1$//$NON-NLS-2$

 		File destinationFile = new File(destination, root.getPath());

 		if (destinationFile.exists())
 			if (overwrite)
 				deleteAll(destinationFile);
 			else
 				throw new IOException("Destination: " + destinationFile + " already exists"); //$NON-NLS-1$//$NON-NLS-2$
 		if (sourceFile.isDirectory()) {
 			destinationFile.mkdirs();
 			File[] list = sourceFile.listFiles();
 			for (int i = 0; i < list.length; i++)
 				copy(source, destination, new File(root, list[i].getName()), false);
 		} else {
 			destinationFile.getParentFile().mkdirs();
 			InputStream in = null;
 			OutputStream out = null;
 			try {
 				in = new BufferedInputStream(new FileInputStream(sourceFile));
 				out = new BufferedOutputStream(new FileOutputStream(destinationFile));
 				copyStream(in, false, out, false);
 			} finally {
 				try {
 					if (in != null)
 						in.close();
 				} finally {
 					if (out != null)
 						out.close();
 				}
 			}
 		}
 	}

 	/**
 	 * Creates a zip archive at the given destination that contains all of the given inclusions
 	 * except for the given exclusions.  Inclusions and exclusions can be phrased as files or folders.
 	 * Including a folder implies that all files and folders under the folder
 	 * should be considered for inclusion. Excluding a folder implies that all files and folders
 	 * under that folder will be excluded. Inclusions with paths deeper than an exclusion folder
 	 * are filtered out and do not end up in the resultant archive.
 	 * <p>
 	 * All entries in the archive are computed using the given path computer.  the path computer
 	 * is reset between every explicit entry in the inclusions list.
 	 * </p>
 	 * @param inclusions the set of files and folders to be considered for inclusion in the result
 	 * @param exclusions the set of files and folders to be excluded from the result.  May be <code>null</code>.
 	 * @param destinationArchive the location of the resultant archive
 	 * @param pathComputer the path computer used to create the path of the files in the result
 	 * @throws IOException if there is an IO issue during this operation.
 	 */
 	public static void zip(File[] inclusions, File[] exclusions, File destinationArchive, IPathComputer pathComputer) throws IOException {
 		FileOutputStream fileOutput = new FileOutputStream(destinationArchive);
 		ZipOutputStream output = new ZipOutputStream(fileOutput);
 		HashSet exclusionSet = exclusions == null ? new HashSet() : new HashSet(Arrays.asList(exclusions));
 		try {
 			for (int i = 0; i < inclusions.length; i++) {
 				pathComputer.reset();
 				zip(output, inclusions[i], exclusionSet, pathComputer);
 			}
 		} finally {
 			try {
 				output.close();
 			} catch (IOException e) {
 				// closing a zip file with no entries apparently fails on some JREs.
 				// if we failed closing the zip, try closing the raw file.
 				try {
 					fileOutput.close();
 				} catch (IOException e2) {
 					// give up.
 				}
 			}
 		}
 	}

 	private static void zip(ZipOutputStream output, File source, Set exclusions, IPathComputer pathComputer) throws IOException {
 		if (exclusions.contains(source))
 			return;
 		if (source.isDirectory()) //if the file path is a URL then isDir and isFile are both false
 			zipDir(output, source, exclusions, pathComputer);
 		else
 			zipFile(output, source, pathComputer);
 	}

 	/*
 	 * Zip the contents of the given directory into the zip file represented by
 	 * the given zip stream. Prepend the given prefix to the file paths.
 	 */
 	private static void zipDir(ZipOutputStream output, File source, Set exclusions, IPathComputer pathComputer) throws IOException {
 		File[] files = source.listFiles();
 		if (files.length == 0) {
 			try {
 				ZipEntry dirEntry = new ZipEntry(pathComputer.computePath(source).toString() + "/"); //$NON-NLS-1$
 				dirEntry.setTime(source.lastModified());
 				output.putNextEntry(dirEntry);
 			} catch (ZipException ze) {
 				//TODO: something about duplicate entries
 			} finally {
 				try {
 					output.closeEntry();
 				} catch (IOException e) {
 					// ignore
 				}
 			}
 		}
 		for (int i = 0; i < files.length; i++)
 			zip(output, files[i], exclusions, pathComputer);
 	}

 	/*
 	 * Add the given file to the zip file represented by the specified stream.
 	 * Prepend the given prefix to the path of the file.
 	 */
 	private static void zipFile(ZipOutputStream output, File source, IPathComputer pathComputer) throws IOException {
 		InputStream input = new FileInputStream(source);
 		try {
 			IPath entryPath = pathComputer.computePath(source);
 			if (entryPath.segmentCount() == 0)
 				throw new IOException("Cannot have an empty zip entry."); //$NON-NLS-1$
 			ZipEntry zipEntry = new ZipEntry(entryPath.toString());
 			zipEntry.setTime(source.lastModified());
 			output.putNextEntry(zipEntry);
 			copyStream(input, true, output, false);
 		} catch (ZipException ze) {
 			//TODO: something about duplicate entries, and rethrow other exceptions
 		} finally {
 			try {
 				input.close();
 			} catch (IOException e) {
 				// ignore
 			}
 			try {
 				output.closeEntry();
 			} catch (IOException e) {
 				// ignore
 			}
 		}
 	}

 	/**
 	 * Path computers are used to transform a given File path into a path suitable for use
 	 * as the to identify that file in an archive file or copy.
 	 */
 	public static interface IPathComputer {
 		/**
 		 * Returns the path representing the given file.  Often this trims or otherwise
 		 * transforms the segments of the source file path.
 		 * @param source the file path to be transformed
 		 * @return the transformed path
 		 */
 		public IPath computePath(File source);

 		/**
 		 * Resets this path computer. Path computers can accumulate state or other information
 		 * for use in computing subsequent paths.  Resetting a computer causes it to flush that
 		 * state and start afresh.  The exact semantics of resetting depends on the nature of the
 		 * computer itself.
 		 */
 		public void reset();
 	}

 	/**
 	 * Creates a path computer that trims all paths according to the given root path.
 	 * Paths that have no matching segments are returned unchanged.
 	 * @param root the base path to use for trimming
 	 * @return a path computer that trims according to the given root
 	 */
 	public static IPathComputer createRootPathComputer(final File root) {
 		return new IPathComputer() {
 			public IPath computePath(File source) {
 				IPath result = new Path(source.getAbsolutePath());
 				IPath rootPath = new Path(root.getAbsolutePath());
 				result = result.removeFirstSegments(rootPath.matchingFirstSegments(result));
 				return result.setDevice(null);
 			}

 			public void reset() {
 				//nothing
 			}
 		};
 	}

 	/**
 	 * Creates a path computer that is a cross between the root and parent computers.
 	 * When this computer is reset, the first path seen is considered a new root.  That path
 	 * is trimmed by the given number of segments and then used as in the same way as the
 	 * root path computer.  Every time this computer is reset, a new root is computed.
 	 * <p>
 	 * This is useful when handling several sets of disjoint files but for each set you want
 	 * to have a common root.  Rather than having to compute the roots ahead of time and
 	 * then manage their relationships, you can simply reset the computer between groups.
 	 * </p><p>
 	 * For example, say you have the a list of folders { /a/b/c/eclipse/plugins/, /x/y/eclipse/features/}
 	 * and want to end up with a zip containing plugins and features folders.  Using a dynamic
 	 * path computer and keeping 1 segment allows this to be done simply by resetting the computer
 	 * between elements of the top level list.
 	 * </p>
 	 * @param segmentsToKeep the number of segments of encountered paths to keep
 	 * relative to the dynamically computed roots.
 	 * @return a path computer that trims but keeps the given number of segments  relative
 	 * to the dynamically computed roots.
 	 */
 	public static IPathComputer createDynamicPathComputer(final int segmentsToKeep) {
 		return new IPathComputer() {
 			IPathComputer computer = null;

 			public IPath computePath(File source) {
 				if (computer == null) {
 					IPath sourcePath = new Path(source.getAbsolutePath());
 					sourcePath = sourcePath.removeLastSegments(segmentsToKeep);
 					computer = createRootPathComputer(sourcePath.toFile());
 				}
 				return computer.computePath(source);
 			}

 			public void reset() {
 				computer = null;
 			}
 		};
 	}

 	/**
 	 * Creates a path computer that retains the given number of trailing segments.
 	 * @param segmentsToKeep number of segments to keep
 	 * @return a path computer that retains the given number of trailing segments.
 	 */
 	public static IPathComputer createParentPrefixComputer(final int segmentsToKeep) {
 		return new IPathComputer() {
 			public IPath computePath(File source) {
 				IPath sourcePath = new Path(source.getAbsolutePath());
 				sourcePath = sourcePath.removeFirstSegments(Math.max(0, sourcePath.segmentCount() - segmentsToKeep));
 				return sourcePath.setDevice(null);
 			}

 			public void reset() {
 				//nothing
 			}
 		};
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2007 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.core.helpers;

	import java.io.*;
	import java.util.*;
	import java.util.zip.*;
	import org.eclipse.core.runtime.*;
	import org.eclipse.osgi.util.NLS;

	public class FileUtils {

	private static File[] untarFile(File source, File outputDir) throws IOException, TarException {
	TarFile tarFile = new TarFile(source);
	List untarredFiles = new ArrayList();
	for (Enumeration e = tarFile.entries(); e.hasMoreElements();) {
	TarEntry entry = (TarEntry) e.nextElement();
	InputStream input = tarFile.getInputStream(entry);
	try {
	File outFile = new File(outputDir, entry.getName());
	untarredFiles.add(outFile);
	if (entry.getFileType() == TarEntry.DIRECTORY) {
	outFile.mkdirs();
	} else {
	if (outFile.exists())
	outFile.delete();
	else
	outFile.getParentFile().mkdirs();
	try {
	copyStream(input, false, new FileOutputStream(outFile), true);
	} catch (FileNotFoundException e1) {
	// TEMP: ignore this for now in case we're trying to replace
	// a running eclipse.exe
	}
	outFile.setLastModified(entry.getTime());
	}
	} finally {
	input.close();
	}
	}
	return (File[]) untarredFiles.toArray(new File[untarredFiles.size()]);
	}

	/**
	* Unzip from a File to an output directory.
	*/
	public static File[] unzipFile(File zipFile, File outputDir) throws IOException {
	// check to see if we have a tar'd and gz'd file
	if (zipFile.getName().toLowerCase().endsWith(".tar.gz")) { //$NON-NLS-1$
	try {
	return untarFile(zipFile, outputDir);
	} catch (TarException e) {
	throw new IOException(e.getMessage());
	}
	}
	InputStream in = new FileInputStream(zipFile);
	try {
	return unzipStream(in, zipFile.length(), outputDir, null, null);
	} catch (IOException e) {
	// add the file name to the message
	throw new IOException(NLS.bind(Messages.Util_Error_Unzipping, zipFile, e.getMessage()));
	} finally {
	in.close();
	}
	}

	/**
	* Unzip from a File to an output directory, with progress indication.
	* monitor may be null.
	*/
	public static File[] unzipFile(File zipFile, File outputDir, String taskName, IProgressMonitor monitor) throws IOException {
	InputStream in = new FileInputStream(zipFile);
	try {
	return unzipStream(in, zipFile.length(), outputDir, taskName, monitor);
	} catch (IOException e) {
	// add the file name to the message
	throw new IOException(NLS.bind(Messages.Util_Error_Unzipping, zipFile, e.getMessage()));
	} finally {
	in.close();
	}
	}

	/**
	* Unzip from an InputStream to an output directory.
	*/
	public static File[] unzipStream(InputStream stream, long size, File outputDir, String taskName, IProgressMonitor monitor) throws IOException {
	InputStream is = monitor == null ? stream : stream; // new ProgressMonitorInputStream(stream, size, size, taskName, monitor); TODO Commented code
	ZipInputStream in = new ZipInputStream(new BufferedInputStream(is));
	ZipEntry ze = in.getNextEntry();
	if (ze == null) {
	// There must be at least one entry in a zip file.
	// When there isn't getNextEntry returns null.
	in.close();
	throw new IOException(Messages.Util_Invalid_Zip_File_Format);
	}
	ArrayList unzippedFiles = new ArrayList();
	do {
	File outFile = new File(outputDir, ze.getName());
	unzippedFiles.add(outFile);
	if (ze.isDirectory()) {
	outFile.mkdirs();
	} else {
	if (outFile.exists()) {
	outFile.delete();
	} else {
	outFile.getParentFile().mkdirs();
	}
	try {
	copyStream(in, false, new FileOutputStream(outFile), true);
	} catch (FileNotFoundException e) {
	// TEMP: ignore this for now in case we're trying to replace
	// a running eclipse.exe
	}
	outFile.setLastModified(ze.getTime());
	}
	in.closeEntry();
	} while ((ze = in.getNextEntry()) != null);
	in.close();

	return (File[]) unzippedFiles.toArray(new File[unzippedFiles.size()]);
	}

	// Delete empty directories under dir, including dir itself.
	public static void deleteEmptyDirs(File dir) throws IOException {
	File[] files = dir.listFiles();
	if (files != null) {
	for (int i = 0; i < files.length; i += 1) {
	deleteEmptyDirs(files[i]);
	}
	dir.getCanonicalFile().delete();
	}
	}

	// Delete the given file whether it is a file or a directory
	public static void deleteAll(File file) {
	if (!file.exists())
	return;
	if (file.isDirectory()) {
	File[] files = file.listFiles();
	if (files != null)
	for (int i = 0; i < files.length; i++)
	deleteAll(files[i]);
	}
	file.delete();
	}

	/**
	* Copy an input stream to an output stream.
	* Optionally close the streams when done.
	* Return the number of bytes written.
	*/
	public static int copyStream(InputStream in, boolean closeIn, OutputStream out, boolean closeOut) throws IOException {
	try {
	int written = 0;
	byte[] buffer = new byte[16 * 1024];
	int len;
	while ((len = in.read(buffer)) != -1) {
	out.write(buffer, 0, len);
	written += len;
	}
	return written;
	} finally {
	try {
	if (closeIn) {
	in.close();
	}
	} finally {
	if (closeOut) {
	out.close();
	}
	}
	}
	}

	public static void copy(File source, File destination, File root, boolean overwrite) throws IOException {
	File sourceFile = new File(source, root.getPath());
	if (!sourceFile.exists())
	throw new FileNotFoundException("Source: " + sourceFile + " does not exist"); //$NON-NLS-1$//$NON-NLS-2$

	File destinationFile = new File(destination, root.getPath());

	if (destinationFile.exists())
	if (overwrite)
	deleteAll(destinationFile);
	else
	throw new IOException("Destination: " + destinationFile + " already exists"); //$NON-NLS-1$//$NON-NLS-2$
	if (sourceFile.isDirectory()) {
	destinationFile.mkdirs();
	File[] list = sourceFile.listFiles();
	for (int i = 0; i < list.length; i++)
	copy(source, destination, new File(root, list[i].getName()), false);
	} else {
	destinationFile.getParentFile().mkdirs();
	InputStream in = null;
	OutputStream out = null;
	try {
	in = new BufferedInputStream(new FileInputStream(sourceFile));
	out = new BufferedOutputStream(new FileOutputStream(destinationFile));
	copyStream(in, false, out, false);
	} finally {
	try {
	if (in != null)
	in.close();
	} finally {
	if (out != null)
	out.close();
	}
	}
	}
	}

	/**
	* Creates a zip archive at the given destination that contains all of the given inclusions
	* except for the given exclusions. Inclusions and exclusions can be phrased as files or folders.
	* Including a folder implies that all files and folders under the folder
	* should be considered for inclusion. Excluding a folder implies that all files and folders
	* under that folder will be excluded. Inclusions with paths deeper than an exclusion folder
	* are filtered out and do not end up in the resultant archive.
	* <p>
	* All entries in the archive are computed using the given path computer. the path computer
	* is reset between every explicit entry in the inclusions list.
	* </p>
	* @param inclusions the set of files and folders to be considered for inclusion in the result
	* @param exclusions the set of files and folders to be excluded from the result. May be <code>null</code>.
	* @param destinationArchive the location of the resultant archive
	* @param pathComputer the path computer used to create the path of the files in the result
	* @throws IOException if there is an IO issue during this operation.
	*/
	public static void zip(File[] inclusions, File[] exclusions, File destinationArchive, IPathComputer pathComputer) throws IOException {
	FileOutputStream fileOutput = new FileOutputStream(destinationArchive);
	ZipOutputStream output = new ZipOutputStream(fileOutput);
	HashSet exclusionSet = exclusions == null ? new HashSet() : new HashSet(Arrays.asList(exclusions));
	try {
	for (int i = 0; i < inclusions.length; i++) {
	pathComputer.reset();
	zip(output, inclusions[i], exclusionSet, pathComputer);
	}
	} finally {
	try {
	output.close();
	} catch (IOException e) {
	// closing a zip file with no entries apparently fails on some JREs.
	// if we failed closing the zip, try closing the raw file.
	try {
	fileOutput.close();
	} catch (IOException e2) {
	// give up.
	}
	}
	}
	}

	private static void zip(ZipOutputStream output, File source, Set exclusions, IPathComputer pathComputer) throws IOException {
	if (exclusions.contains(source))
	return;
	if (source.isDirectory()) //if the file path is a URL then isDir and isFile are both false
	zipDir(output, source, exclusions, pathComputer);
	else
	zipFile(output, source, pathComputer);
	}

	/*
	* Zip the contents of the given directory into the zip file represented by
	* the given zip stream. Prepend the given prefix to the file paths.
	*/
	private static void zipDir(ZipOutputStream output, File source, Set exclusions, IPathComputer pathComputer) throws IOException {
	File[] files = source.listFiles();
	if (files.length == 0) {
	try {
	ZipEntry dirEntry = new ZipEntry(pathComputer.computePath(source).toString() + "/"); //$NON-NLS-1$
	dirEntry.setTime(source.lastModified());
	output.putNextEntry(dirEntry);
	} catch (ZipException ze) {
	//TODO: something about duplicate entries
	} finally {
	try {
	output.closeEntry();
	} catch (IOException e) {
	// ignore
	}
	}
	}
	for (int i = 0; i < files.length; i++)
	zip(output, files[i], exclusions, pathComputer);
	}

	/*
	* Add the given file to the zip file represented by the specified stream.
	* Prepend the given prefix to the path of the file.
	*/
	private static void zipFile(ZipOutputStream output, File source, IPathComputer pathComputer) throws IOException {
	InputStream input = new FileInputStream(source);
	try {
	IPath entryPath = pathComputer.computePath(source);
	if (entryPath.segmentCount() == 0)
	throw new IOException("Cannot have an empty zip entry."); //$NON-NLS-1$
	ZipEntry zipEntry = new ZipEntry(entryPath.toString());
	zipEntry.setTime(source.lastModified());
	output.putNextEntry(zipEntry);
	copyStream(input, true, output, false);
	} catch (ZipException ze) {
	//TODO: something about duplicate entries, and rethrow other exceptions
	} finally {
	try {
	input.close();
	} catch (IOException e) {
	// ignore
	}
	try {
	output.closeEntry();
	} catch (IOException e) {
	// ignore
	}
	}
	}

	/**
	* Path computers are used to transform a given File path into a path suitable for use
	* as the to identify that file in an archive file or copy.
	*/
	public static interface IPathComputer {
	/**
	* Returns the path representing the given file. Often this trims or otherwise
	* transforms the segments of the source file path.
	* @param source the file path to be transformed
	* @return the transformed path
	*/
	public IPath computePath(File source);

	/**
	* Resets this path computer. Path computers can accumulate state or other information
	* for use in computing subsequent paths. Resetting a computer causes it to flush that
	* state and start afresh. The exact semantics of resetting depends on the nature of the
	* computer itself.
	*/
	public void reset();
	}

	/**
	* Creates a path computer that trims all paths according to the given root path.
	* Paths that have no matching segments are returned unchanged.
	* @param root the base path to use for trimming
	* @return a path computer that trims according to the given root
	*/
	public static IPathComputer createRootPathComputer(final File root) {
	return new IPathComputer() {
	public IPath computePath(File source) {
	IPath result = new Path(source.getAbsolutePath());
	IPath rootPath = new Path(root.getAbsolutePath());
	result = result.removeFirstSegments(rootPath.matchingFirstSegments(result));
	return result.setDevice(null);
	}

	public void reset() {
	//nothing
	}
	};
	}

	/**
	* Creates a path computer that is a cross between the root and parent computers.
	* When this computer is reset, the first path seen is considered a new root. That path
	* is trimmed by the given number of segments and then used as in the same way as the
	* root path computer. Every time this computer is reset, a new root is computed.
	* <p>
	* This is useful when handling several sets of disjoint files but for each set you want
	* to have a common root. Rather than having to compute the roots ahead of time and
	* then manage their relationships, you can simply reset the computer between groups.
	* </p><p>
	* For example, say you have the a list of folders { /a/b/c/eclipse/plugins/, /x/y/eclipse/features/}
	* and want to end up with a zip containing plugins and features folders. Using a dynamic
	* path computer and keeping 1 segment allows this to be done simply by resetting the computer
	* between elements of the top level list.
	* </p>
	* @param segmentsToKeep the number of segments of encountered paths to keep
	* relative to the dynamically computed roots.
	* @return a path computer that trims but keeps the given number of segments relative
	* to the dynamically computed roots.
	*/
	public static IPathComputer createDynamicPathComputer(final int segmentsToKeep) {
	return new IPathComputer() {
	IPathComputer computer = null;

	public IPath computePath(File source) {
	if (computer == null) {
	IPath sourcePath = new Path(source.getAbsolutePath());
	sourcePath = sourcePath.removeLastSegments(segmentsToKeep);
	computer = createRootPathComputer(sourcePath.toFile());
	}
	return computer.computePath(source);
	}

	public void reset() {
	computer = null;
	}
	};
	}

	/**
	* Creates a path computer that retains the given number of trailing segments.
	* @param segmentsToKeep number of segments to keep
	* @return a path computer that retains the given number of trailing segments.
	*/
	public static IPathComputer createParentPrefixComputer(final int segmentsToKeep) {
	return new IPathComputer() {
	public IPath computePath(File source) {
	IPath sourcePath = new Path(source.getAbsolutePath());
	sourcePath = sourcePath.removeFirstSegments(Math.max(0, sourcePath.segmentCount() - segmentsToKeep));
	return sourcePath.setDevice(null);
	}

	public void reset() {
	//nothing
	}
	};
	}
	}