diff --git a/Documentation/developer-guide.md b/Documentation/developer-guide.md
index d36a24d..0a96b3a 100644
--- a/Documentation/developer-guide.md
+++ b/Documentation/developer-guide.md
@@ -67,8 +67,8 @@
 ```
 
 This will recompile and start a development server.  Open
-http://localhost:8080/ to view your local copy of gitiles, which
-will serve any repositories under `/path/to/repositories`.
+http://localhost:8080/path/to/repositories to view your local copy of gitiles,
+which will serve any repositories under `/path/to/repositories`.
 
 Passing `--debug` option to `tools/run_dev.sh` will suspend the runtime until a
 remote debugger connects to port 5005. If you don't want to suspend the
diff --git a/java/com/google/gitiles/LogServlet.java b/java/com/google/gitiles/LogServlet.java
index 71f7384..368fd0b 100644
--- a/java/com/google/gitiles/LogServlet.java
+++ b/java/com/google/gitiles/LogServlet.java
@@ -191,10 +191,14 @@
     if (headRef == null) {
       return null;
     }
+    ObjectId id = headRef.getObjectId();
+    if (id == null) {
+      return null;
+    }
     try (RevWalk walk = new RevWalk(repo)) {
       return GitilesView.log()
           .copyFrom(view)
-          .setRevision(Revision.peel(Constants.HEAD, walk.parseAny(headRef.getObjectId()), walk))
+          .setRevision(Revision.peel(Constants.HEAD, walk.parseAny(id), walk))
           .build();
     }
   }