diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectChecker.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectChecker.java
index 14cb52898..6e470c9b2 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectChecker.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectChecker.java
@@ -346,15 +346,7 @@ public class ObjectChecker {
 				if (c == '/')
 					throw new CorruptObjectException("name contains '/'");
 			}
-			if (thisNameB + 1 == ptr)
-				throw new CorruptObjectException("zero length name");
-			if (raw[thisNameB] == '.') {
-				final int nameLen = (ptr - 1) - thisNameB;
-				if (nameLen == 1)
-					throw new CorruptObjectException("invalid name '.'");
-				if (nameLen == 2 && raw[thisNameB + 1] == '.')
-					throw new CorruptObjectException("invalid name '..'");
-			}
+			checkPathSegment(raw, thisNameB, ptr - 1);
 			if (duplicateName(raw, thisNameB, ptr - 1))
 				throw new CorruptObjectException("duplicate entry names");
 
@@ -375,6 +367,19 @@ public class ObjectChecker {
 		}
 	}
 
+	private static void checkPathSegment(byte[] raw, int ptr, int end)
+			throws CorruptObjectException {
+		if (ptr == end)
+			throw new CorruptObjectException("zero length name");
+		if (raw[ptr] == '.') {
+			int nameLen = end - ptr;
+			if (nameLen == 1)
+				throw new CorruptObjectException("invalid name '.'");
+			if (nameLen == 2 && raw[ptr + 1] == '.')
+				throw new CorruptObjectException("invalid name '..'");
+		}
+	}
+
 	/**
 	 * Check a blob for errors.
 	 *