src/org/nbgit/client/CheckoutBuilder.java

   1 /*
   2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
   3  *
   4  * Copyright 2009 Jonas Fonseca <fonseca@diku.dk>
   5  *
   6  * The contents of this file are subject to the terms of either the GNU
   7  * General Public License Version 2 only ("GPL") or the Common
   8  * Development and Distribution License("CDDL") (collectively, the
   9  * "License"). You may not use this file except in compliance with the
  10  * License. You can obtain a copy of the License at
  11  * http://www.netbeans.org/cddl-gplv2.html. See the License for the
  12  * specific language governing permissions and limitations under the
  13  * License.  When distributing the software, include this License Header
  14  * Notice in each file.
  15  *
  16  * This particular file is subject to the "Classpath" exception as provided
  17  * by Sun in the GPL Version 2 section of the License file that
  18  * accompanied this code. If applicable, add the following below the
  19  * License Header, with the fields enclosed by brackets [] replaced by
  20  * your own identifying information:
  21  * "Portions Copyrighted [year] [name of copyright owner]"
  22  *
  23  * Contributor(s):
  24  *
  25  * If you wish your version of this file to be governed by only the CDDL
  26  * or only the GPL Version 2, indicate your decision by adding
  27  * "[Contributor] elects to include this software in this distribution
  28  * under the [CDDL or GPL Version 2] license." If you do not indicate a
  29  * single choice of license, a recipient has the option to distribute
  30  * your version of this file under either the CDDL, the GPL Version 2 or
  31  * to extend the choice of license to its licensees as provided above.
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  33  * Version 2 license, then the option applies only if the new code is
  34  * made subject to such option by the copyright holder.
  35  */
  36 package org.nbgit.client;
  37
  38 import java.io.File;
  39 import java.io.FileNotFoundException;
  40 import java.io.FileOutputStream;
  41 import java.io.IOException;
  42 import java.nio.ByteBuffer;
  43 import java.nio.channels.FileChannel;
  44 import java.util.Collection;
  45 import java.util.HashMap;
  46 import java.util.Map;
  47 import org.spearce.jgit.lib.FileMode;
  48 import org.spearce.jgit.lib.GitIndex;
  49 import org.spearce.jgit.lib.ObjectId;
  50 import org.spearce.jgit.lib.Repository;
  51 import org.spearce.jgit.lib.Tree;
  52 import org.spearce.jgit.lib.TreeEntry;
  53
  54 /**
  55  * Build a checkout of files from a revision.
  56  */
  57 public class CheckoutBuilder extends ClientBuilder {
  58
  59     private static final String BACKUP_EXT = ".orig";
  60     private final HashMap<RevisionEntry, File> fileMappings = new HashMap<RevisionEntry, File>();
  61     private boolean backup;
  62     private Tree tree;
  63     private GitIndex index;
  64
  65     private CheckoutBuilder(Repository repository) {
  66         super(repository);
  67     }
  68
  69     /**
  70      * Create builder for repository.
  71      *
  72      * @param repository to use for the builder.
  73      * @return the builder.
  74      */
  75     public static CheckoutBuilder create(Repository repository) {
  76         return new CheckoutBuilder(repository);
  77     }
  78
  79     /**
  80      * Create builder from working directory.
  81      *
  82      * @param workDir of the repository.
  83      * @return the builder.
  84      * @throws IOException if loading the repository fails.
  85      */
  86     public static CheckoutBuilder create(File workDir) throws IOException {
  87         return create(toRepository(workDir));
  88     }
  89
  90     /**
  91      * Set revision to check out.
  92      *
  93      * @param revision to checkout.
  94      * @return the builder.
  95      * @throws IOException if the builder fails to load the revision.
  96      * @throws IllegalArgumentException if the builder fails to resolve
  97      *  the revision.
  98      */
  99     public CheckoutBuilder revision(String revision)
 100             throws IOException, IllegalArgumentException {
 101         tree = repository.mapTree(revision);
 102         if (tree == null)
 103             throw new IllegalArgumentException(revision);
 104         return this;
 105     }
 106
 107     /**
 108      * Set file to be checked out to a specific destination.
 109      *
 110      * @param file to be checked out.
 111      * @param destination where the file should be checked out.
 112      * @return the builder.
 113      * @throws FileNotFoundException if the file cannot be resolved.
 114      * @throws IOException if checking of file existance fails.
 115      */
 116     public CheckoutBuilder file(File file, File destination)
 117             throws IOException, FileNotFoundException {
 118         String path = toPath(file);
 119         ObjectId blobId = null;
 120         int modeBits = 0;
 121
 122         if (tree != null) {
 123             TreeEntry entry = tree.findBlobMember(path);
 124             if (entry != null) {
 125                 blobId = entry.getId();
 126                 modeBits = entry.getMode().getBits();
 127             }
 128         } else {
 129             if (index == null)
 130                 index = repository.getIndex();
 131             GitIndex.Entry entry = index.getEntry(path);
 132             if (entry != null) {
 133                 blobId = entry.getObjectId();
 134                 modeBits = entry.getModeBits();
 135             }
 136         }
 137         if (blobId == null)
 138             throw new FileNotFoundException(path);
 139         fileMappings.put(RevisionEntry.create(path, blobId, modeBits), destination);
 140         return this;
 141     }
 142
 143     /**
 144      * Set files to be checked out. The destination of the files will be the
 145      * path of the file, which means their path relative to the repository's
 146      * working directory.
 147      *
 148      * @param files to be checked out.
 149      * @return the builder.
 150      * @throws FileNotFoundException if the file cannot be resolved.
 151      * @throws IOException if checking of file existance fails.
 152      */
 153     public CheckoutBuilder files(Collection<File> files)
 154             throws IOException, FileNotFoundException {
 155         for (File file : files) {
 156             file(file, file);
 157         }
 158         return this;
 159     }
 160
 161     /**
 162      * Whether to backup existing files that would otherwise be overwritten.
 163      *
 164      * @param backup files?
 165      * @return the builder.
 166      */
 167     public CheckoutBuilder backup(boolean backup) {
 168         this.backup = backup;
 169         return this;
 170     }
 171
 172     /**
 173      * Perform the checkout. Non-existing files added before a revision
 174      * was set will be ignored.
 175      *
 176      * @throws IOException if the checkout fails.
 177      */
 178     public void checkout() throws IOException {
 179         for (Map.Entry<RevisionEntry, File> mapping : fileMappings.entrySet()) {
 180             RevisionEntry entry = mapping.getKey();
 181             File file = mapping.getValue();
 182             if (backup)
 183                 backupFile(file);
 184             checkoutEntry(entry.getObjectId(), entry.getModeBits(), file);
 185         }
 186     }
 187
 188     private void backupFile(File file) throws IOException {
 189         String extension = BACKUP_EXT;
 190
 191         for (int i = 0; i < 1024; i++) {
 192             File backupFile = new File(file.getAbsolutePath() + extension);
 193             if (!backupFile.exists()) {
 194                 file.renameTo(backupFile);
 195                 break;
 196             }
 197             extension = "." + i + BACKUP_EXT;
 198         }
 199     }
 200
 201     /*
 202      * Code originally from GitIndex.
 203      */
 204     private void checkoutEntry(ObjectId blobId, int modeBits, File file) throws IOException {
 205         file.delete();
 206         file.getParentFile().mkdirs();
 207
 208         FileChannel channel = new FileOutputStream(file).getChannel();
 209         try {
 210             byte[] bytes = repository.openBlob(blobId).getBytes();
 211             ByteBuffer buffer = ByteBuffer.wrap(bytes);
 212             if (channel.write(buffer) != bytes.length)
 213                 throw new IOException("Could not write file " + file);
 214         } finally {
 215             channel.close();
 216         }
 217         setExecutable(file, FileMode.EXECUTABLE_FILE.equals(modeBits));
 218     }
 219 }