Java tutorial
/* * Copyright 2012 gitblit.com. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.gitblit.utils; import java.io.IOException; import java.io.OutputStream; import java.text.MessageFormat; import java.util.ArrayList; import java.util.List; import org.apache.commons.compress.archivers.tar.TarArchiveEntry; import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream; import org.apache.commons.compress.archivers.zip.ZipArchiveEntry; import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream; import org.apache.commons.compress.compressors.CompressorException; import org.apache.commons.compress.compressors.CompressorStreamFactory; import org.apache.wicket.util.io.ByteArrayOutputStream; import org.eclipse.jgit.lib.Constants; import org.eclipse.jgit.lib.FileMode; import org.eclipse.jgit.lib.MutableObjectId; import org.eclipse.jgit.lib.ObjectLoader; import org.eclipse.jgit.lib.ObjectReader; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.revwalk.RevCommit; import org.eclipse.jgit.revwalk.RevWalk; import org.eclipse.jgit.treewalk.TreeWalk; import org.eclipse.jgit.treewalk.filter.PathFilter; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Collection of static methods for retrieving information from a repository. * * @author James Moger * */ public class CompressionUtils { static final Logger LOGGER = LoggerFactory.getLogger(CompressionUtils.class); /** * Log an error message and exception. * * @param t * @param repository * if repository is not null it MUST be the {0} parameter in the * pattern. * @param pattern * @param objects */ private static void error(Throwable t, Repository repository, String pattern, Object... objects) { List<Object> parameters = new ArrayList<Object>(); if (objects != null && objects.length > 0) { for (Object o : objects) { parameters.add(o); } } if (repository != null) { parameters.add(0, repository.getDirectory().getAbsolutePath()); } LOGGER.error(MessageFormat.format(pattern, parameters.toArray()), t); } /** * Zips the contents of the tree at the (optionally) specified revision and * the (optionally) specified basepath to the supplied outputstream. * * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ public static boolean zip(Repository repository, String basePath, String objectId, OutputStream os) { RevCommit commit = JGitUtils.getCommit(repository, objectId); if (commit == null) { return false; } boolean success = false; RevWalk rw = new RevWalk(repository); TreeWalk tw = new TreeWalk(repository); try { tw.reset(); tw.addTree(commit.getTree()); ZipArchiveOutputStream zos = new ZipArchiveOutputStream(os); zos.setComment("Generated by Gitblit"); if (!StringUtils.isEmpty(basePath)) { PathFilter f = PathFilter.create(basePath); tw.setFilter(f); } tw.setRecursive(true); MutableObjectId id = new MutableObjectId(); ObjectReader reader = tw.getObjectReader(); long modified = commit.getAuthorIdent().getWhen().getTime(); while (tw.next()) { FileMode mode = tw.getFileMode(0); if (mode == FileMode.GITLINK || mode == FileMode.TREE) { continue; } tw.getObjectId(id, 0); ZipArchiveEntry entry = new ZipArchiveEntry(tw.getPathString()); entry.setSize(reader.getObjectSize(id, Constants.OBJ_BLOB)); entry.setComment(commit.getName()); entry.setUnixMode(mode.getBits()); entry.setTime(modified); zos.putArchiveEntry(entry); ObjectLoader ldr = repository.open(id); ldr.copyTo(zos); zos.closeArchiveEntry(); } zos.finish(); success = true; } catch (IOException e) { error(e, repository, "{0} failed to zip files from commit {1}", commit.getName()); } finally { tw.release(); rw.dispose(); } return success; } /** * tar the contents of the tree at the (optionally) specified revision and * the (optionally) specified basepath to the supplied outputstream. * * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ public static boolean tar(Repository repository, String basePath, String objectId, OutputStream os) { return tar(null, repository, basePath, objectId, os); } /** * tar.gz the contents of the tree at the (optionally) specified revision and * the (optionally) specified basepath to the supplied outputstream. * * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ public static boolean gz(Repository repository, String basePath, String objectId, OutputStream os) { return tar(CompressorStreamFactory.GZIP, repository, basePath, objectId, os); } /** * tar.xz the contents of the tree at the (optionally) specified revision and * the (optionally) specified basepath to the supplied outputstream. * * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ public static boolean xz(Repository repository, String basePath, String objectId, OutputStream os) { return tar(CompressorStreamFactory.XZ, repository, basePath, objectId, os); } /** * tar.bzip2 the contents of the tree at the (optionally) specified revision and * the (optionally) specified basepath to the supplied outputstream. * * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ public static boolean bzip2(Repository repository, String basePath, String objectId, OutputStream os) { return tar(CompressorStreamFactory.BZIP2, repository, basePath, objectId, os); } /** * Compresses/archives the contents of the tree at the (optionally) * specified revision and the (optionally) specified basepath to the * supplied outputstream. * * @param algorithm * compression algorithm for tar (optional) * @param repository * @param basePath * if unspecified, entire repository is assumed. * @param objectId * if unspecified, HEAD is assumed. * @param os * @return true if repository was successfully zipped to supplied output * stream */ private static boolean tar(String algorithm, Repository repository, String basePath, String objectId, OutputStream os) { RevCommit commit = JGitUtils.getCommit(repository, objectId); if (commit == null) { return false; } OutputStream cos = os; if (!StringUtils.isEmpty(algorithm)) { try { cos = new CompressorStreamFactory().createCompressorOutputStream(algorithm, os); } catch (CompressorException e1) { error(e1, repository, "{0} failed to open {1} stream", algorithm); } } boolean success = false; RevWalk rw = new RevWalk(repository); TreeWalk tw = new TreeWalk(repository); try { tw.reset(); tw.addTree(commit.getTree()); TarArchiveOutputStream tos = new TarArchiveOutputStream(cos); tos.setAddPaxHeadersForNonAsciiNames(true); tos.setLongFileMode(TarArchiveOutputStream.LONGFILE_POSIX); if (!StringUtils.isEmpty(basePath)) { PathFilter f = PathFilter.create(basePath); tw.setFilter(f); } tw.setRecursive(true); MutableObjectId id = new MutableObjectId(); long modified = commit.getAuthorIdent().getWhen().getTime(); while (tw.next()) { FileMode mode = tw.getFileMode(0); if (mode == FileMode.GITLINK || mode == FileMode.TREE) { continue; } tw.getObjectId(id, 0); ObjectLoader loader = repository.open(id); if (FileMode.SYMLINK == mode) { TarArchiveEntry entry = new TarArchiveEntry(tw.getPathString(), TarArchiveEntry.LF_SYMLINK); ByteArrayOutputStream bos = new ByteArrayOutputStream(); loader.copyTo(bos); entry.setLinkName(bos.toString()); entry.setModTime(modified); tos.putArchiveEntry(entry); tos.closeArchiveEntry(); } else { TarArchiveEntry entry = new TarArchiveEntry(tw.getPathString()); entry.setMode(mode.getBits()); entry.setModTime(modified); entry.setSize(loader.getSize()); tos.putArchiveEntry(entry); loader.copyTo(tos); tos.closeArchiveEntry(); } } tos.finish(); tos.close(); cos.close(); success = true; } catch (IOException e) { error(e, repository, "{0} failed to {1} stream files from commit {2}", algorithm, commit.getName()); } finally { tw.release(); rw.dispose(); } return success; } }