PackWriter: Export more statistics

Export the shallow pack information, and also a handy function to
sum up the total times.  Include the time writing out the index file,
if it was created.

Change-Id: I7f60ae6848455a357b25feedb23743bbf6c153cf
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackWriter.java

@@ -714,6 +714,7 @@ public void writeIndex(final OutputStream indexStream) throws IOException {
 		if (!cachedPacks.isEmpty())
 			throw new IOException(JGitText.get().cachedPacksPreventsIndexCreation);
 
+		long writeStart = System.currentTimeMillis();
 		final List<ObjectToPack> list = sortByName();
 		final PackIndexWriter iw;
 		int indexVersion = config.getIndexVersion();
@@ -722,6 +723,7 @@ public void writeIndex(final OutputStream indexStream) throws IOException {
 		else
 			iw = PackIndexWriter.createVersion(indexStream, indexVersion);
 		iw.write(list, packcsum);
+		stats.timeWriting += System.currentTimeMillis() - writeStart;
 	}
 
 	private List<ObjectToPack> sortByName() {
@@ -828,6 +830,7 @@ public void writePack(ProgressMonitor compressMonitor,
 		stats.timeWriting = System.currentTimeMillis() - writeStart;
 		stats.totalBytes = out.length();
 		stats.reusedPacks = Collections.unmodifiableList(cachedPacks);
+		stats.depth = depth;
 
 		for (Statistics.ObjectType typeStat : stats.objectTypes) {
 			if (typeStat == null)
@@ -1870,6 +1873,8 @@ public long getDeltaBytes() {
 
 		Collection<CachedPack> reusedPacks;
 
+		int depth;
+
 		int deltaSearchNonEdgeObjects;
 
 		int deltasFound;
@@ -2012,6 +2017,16 @@ public ObjectType byObjectType(int typeCode) {
 			return objectTypes[typeCode];
 		}
 
+		/** @return true if the resulting pack file was a shallow pack. */
+		public boolean isShallow() {
+			return depth > 0;
+		}
+
+		/** @return depth (in commits) the pack includes if shallow. */
+		public int getDepth() {
+			return depth;
+		}
+
 		/**
 		 * @return time in milliseconds spent enumerating the objects that need
 		 *         to be included in the output. This time includes any restarts
@@ -2060,6 +2075,15 @@ public long getTimeWriting() {
 			return timeWriting;
 		}
 
+		/** @return total time spent processing this pack. */
+		public long getTimeTotal() {
+			return timeCounting
+				+ timeSearchingForReuse
+				+ timeSearchingForSizes
+				+ timeCompressing
+				+ timeWriting;
+		}
+
 		/**
 		 * @return get the average output speed in terms of bytes-per-second.
 		 *         {@code getTotalBytes() / (getTimeWriting() / 1000.0)}.