Initial JGit contribution to eclipse.org

Per CQ 3448 this is the initial contribution of the JGit project
to eclipse.org.  It is derived from the historical JGit repository
at commit 3a2dd9921c8a08740a9e02c421469e5b1a9e47cb.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 139 insertions, 0 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/revplot/PlotWalk.java b/org.eclipse.jgit/src/org/eclipse/jgit/revplot/PlotWalk.java
new file mode 100644
index 0000000000..bebe148ebb
--- /dev/null
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/revplot/PlotWalk.java
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2008-2009, Robin Rosenberg <robin.rosenberg@dewire.com>
+ * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.revplot;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.Map;
+import java.util.Set;
+
+import org.eclipse.jgit.lib.AnyObjectId;
+import org.eclipse.jgit.lib.Commit;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.lib.Tag;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevSort;
+import org.eclipse.jgit.revwalk.RevWalk;
+
+/** Specialized RevWalk for visualization of a commit graph. */
+public class PlotWalk extends RevWalk {
+
+	private Map<AnyObjectId, Set<Ref>> reverseRefMap;
+
+	@Override
+	public void dispose() {
+		super.dispose();
+		reverseRefMap.clear();
+	}
+
+	/**
+	 * Create a new revision walker for a given repository.
+	 * 
+	 * @param repo
+	 *            the repository the walker will obtain data from.
+	 */
+	public PlotWalk(final Repository repo) {
+		super(repo);
+		super.sort(RevSort.TOPO, true);
+		reverseRefMap = repo.getAllRefsByPeeledObjectId();
+	}
+
+	@Override
+	public void sort(final RevSort s, final boolean use) {
+		if (s == RevSort.TOPO && !use)
+			throw new IllegalArgumentException("Topological sort required.");
+		super.sort(s, use);
+	}
+
+	@Override
+	protected RevCommit createCommit(final AnyObjectId id) {
+		return new PlotCommit(id, getTags(id));
+	}
+
+	/**
+	 * @param commitId
+	 * @return return the list of knows tags referring to this commit
+	 */
+	protected Ref[] getTags(final AnyObjectId commitId) {
+		Collection<Ref> list = reverseRefMap.get(commitId);
+		Ref[] tags;
+		if (list == null)
+			tags = null;
+		else {
+			tags = list.toArray(new Ref[list.size()]);
+			Arrays.sort(tags, new PlotRefComparator());
+		}
+		return tags;
+	}
+
+	class PlotRefComparator implements Comparator<Ref> {
+		public int compare(Ref o1, Ref o2) {
+			try {
+				Object obj1 = getRepository().mapObject(o1.getObjectId(), o1.getName());
+				Object obj2 = getRepository().mapObject(o2.getObjectId(), o2.getName());
+				long t1 = timeof(obj1);
+				long t2 = timeof(obj2);
+				if (t1 > t2)
+					return -1;
+				if (t1 < t2)
+					return 1;
+				return 0;
+			} catch (IOException e) {
+				// ignore
+				return 0;
+			}
+		}
+		long timeof(Object o) {
+			if (o instanceof Commit)
+				return ((Commit)o).getCommitter().getWhen().getTime();
+			if (o instanceof Tag)
+				return ((Tag)o).getTagger().getWhen().getTime();
+			return 0;
+		}
+	}
+}