org.spearce.egit.core/src/org/spearce/egit/core/ContainerTreeIterator.java

   1 /*******************************************************************************
   2  * Copyright (C) 2008, Google Inc.
   3  *
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * See LICENSE for the full license text, also available.
   7  *******************************************************************************/
   8
   9 package org.spearce.egit.core;
  10
  11 import java.io.File;
  12 import java.io.IOException;
  13 import java.io.InputStream;
  14
  15 import org.eclipse.core.resources.IContainer;
  16 import org.eclipse.core.resources.IFile;
  17 import org.eclipse.core.resources.IResource;
  18 import org.eclipse.core.runtime.CoreException;
  19 import org.spearce.egit.core.project.RepositoryMapping;
  20 import org.spearce.jgit.errors.IncorrectObjectTypeException;
  21 import org.spearce.jgit.lib.Constants;
  22 import org.spearce.jgit.lib.FileMode;
  23 import org.spearce.jgit.lib.ObjectId;
  24 import org.spearce.jgit.lib.Repository;
  25 import org.spearce.jgit.treewalk.AbstractTreeIterator;
  26 import org.spearce.jgit.treewalk.WorkingTreeIterator;
  27 import org.spearce.jgit.util.FS;
  28
  29 /**
  30  * Adapts an Eclipse {@link IContainer} for use in a <code>TreeWalk</code>.
  31  * <p>
  32  * This iterator converts an Eclipse IContainer object into something that a
  33  * TreeWalk instance can iterate over in parallel with any other Git tree data
  34  * structure, such as another working directory tree from outside of the
  35  * workspace or a stored tree from a Repository object database.
  36  * <p>
  37  * Modification times provided by this iterator are obtained from the cache
  38  * Eclipse uses to track external resource modification. This can be faster, but
  39  * requires the user refresh their workspace when external modifications take
  40  * place. This is not really a concern as it is common practice to need to do a
  41  * workspace refresh after externally modifying a file.
  42  *
  43  * @see org.spearce.jgit.treewalk.TreeWalk
  44  */
  45 public class ContainerTreeIterator extends WorkingTreeIterator {
  46         private static String computePrefix(final IContainer base) {
  47                 final RepositoryMapping rm = RepositoryMapping.getMapping(base);
  48                 if (rm == null)
  49                         throw new IllegalArgumentException("Not in a Git project: " + base);
  50                 return rm.getRepoRelativePath(base);
  51         }
  52
  53         private final IContainer node;
  54
  55         /**
  56          * Construct a new iterator from the workspace.
  57          * <p>
  58          * The iterator will support traversal over the named container, but only if
  59          * it is contained within a project which has the Git repository provider
  60          * connected and this resource is mapped into a Git repository. During the
  61          * iteration the paths will be automatically generated to match the proper
  62          * repository paths for this container's children.
  63          *
  64          * @param base
  65          *            the part of the workspace the iterator will walk over.
  66          */
  67         public ContainerTreeIterator(final IContainer base) {
  68                 super(computePrefix(base));
  69                 node = base;
  70                 init(entries());
  71         }
  72
  73         private ContainerTreeIterator(final WorkingTreeIterator p,
  74                         final IContainer base) {
  75                 super(p);
  76                 node = base;
  77                 init(entries());
  78         }
  79
  80         @Override
  81         public AbstractTreeIterator createSubtreeIterator(final Repository db)
  82                         throws IncorrectObjectTypeException, IOException {
  83                 if (FileMode.TREE.equals(mode))
  84                         return new ContainerTreeIterator(this,
  85                                         (IContainer) ((ResourceEntry) current()).rsrc);
  86                 else
  87                         throw new IncorrectObjectTypeException(ObjectId.zeroId(),
  88                                         Constants.TYPE_TREE);
  89         }
  90
  91         private Entry[] entries() {
  92                 final IResource[] all;
  93                 try {
  94                         all = node.members(IContainer.INCLUDE_HIDDEN);
  95                 } catch (CoreException err) {
  96                         return EOF;
  97                 }
  98
  99                 final Entry[] r = new Entry[all.length];
 100                 for (int i = 0; i < r.length; i++)
 101                         r[i] = new ResourceEntry(all[i]);
 102                 return r;
 103         }
 104
 105         static class ResourceEntry extends Entry {
 106                 final IResource rsrc;
 107
 108                 private final FileMode mode;
 109
 110                 private long length = -1;
 111
 112                 ResourceEntry(final IResource f) {
 113                         rsrc = f;
 114
 115                         switch (f.getType()) {
 116                         case IResource.FILE:
 117                                 if (FS.INSTANCE.canExecute(asFile()))
 118                                         mode = FileMode.EXECUTABLE_FILE;
 119                                 else
 120                                         mode = FileMode.REGULAR_FILE;
 121                                 break;
 122                         case IResource.FOLDER: {
 123                                 final IContainer c = (IContainer) f;
 124                                 if (c.findMember(".git") != null)
 125                                         mode = FileMode.GITLINK;
 126                                 else
 127                                         mode = FileMode.TREE;
 128                                 break;
 129                         }
 130                         default:
 131                                 mode = FileMode.MISSING;
 132                                 break;
 133                         }
 134                 }
 135
 136                 @Override
 137                 public FileMode getMode() {
 138                         return mode;
 139                 }
 140
 141                 @Override
 142                 public String getName() {
 143                         return rsrc.getName();
 144                 }
 145
 146                 @Override
 147                 public long getLength() {
 148                         if (length < 0) {
 149                                 if (rsrc instanceof IFile)
 150                                         length = asFile().length();
 151                                 else
 152                                         length = 0;
 153                         }
 154                         return length;
 155                 }
 156
 157                 @Override
 158                 public long getLastModified() {
 159                         return rsrc.getLocalTimeStamp();
 160                 }
 161
 162                 @Override
 163                 public InputStream openInputStream() throws IOException {
 164                         if (rsrc instanceof IFile) {
 165                                 try {
 166                                         return ((IFile) rsrc).getContents(true);
 167                                 } catch (CoreException err) {
 168                                         final IOException ioe = new IOException(err.getMessage());
 169                                         ioe.initCause(err);
 170                                         throw ioe;
 171                                 }
 172                         }
 173                         throw new IOException("Not a regular file: " + rsrc);
 174                 }
 175
 176                 private File asFile() {
 177                         return ((IFile) rsrc).getLocation().toFile();
 178                 }
 179         }
 180 }