diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftree/RefTreeBatch.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftree/RefTreeBatch.java
index c5560b97b..b154b95ad 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftree/RefTreeBatch.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftree/RefTreeBatch.java
@@ -88,8 +88,9 @@ void init(RevWalk rw) throws IOException {
 			tree = RefTree.read(rw.getObjectReader(), c.getTree());
 		} else {
 			parentCommitId = ObjectId.zeroId();
-			parentTreeId = new ObjectInserter.Formatter()
-					.idFor(OBJ_TREE, new byte[] {});
+			try (ObjectInserter.Formatter fmt = new ObjectInserter.Formatter()) {
+				parentTreeId = fmt.idFor(OBJ_TREE, new byte[] {});
+			}
 			tree = RefTree.newEmptyTree();
 		}
 	}