Index: src/Common/NetTopologySuite/Algorithm/CentroidLine.cs
===================================================================
diff -u -r8f6ae890fed8e8eae3a32f9c0498a10f82e0ddf9 -r5fc71a385897af92ccb092f2f969b5709afab85a
--- src/Common/NetTopologySuite/Algorithm/CentroidLine.cs	(.../CentroidLine.cs)	(revision 8f6ae890fed8e8eae3a32f9c0498a10f82e0ddf9)
+++ src/Common/NetTopologySuite/Algorithm/CentroidLine.cs	(.../CentroidLine.cs)	(revision 5fc71a385897af92ccb092f2f969b5709afab85a)
@@ -11,46 +11,50 @@
     /// </summary>
     public class CentroidLine
     {
-        private ICoordinate centSum = new Coordinate();
+        private readonly ICoordinate centSum = new Coordinate();
         private double totalLength = 0.0;
 
         /// <summary>
         /// 
         /// </summary>
-        public CentroidLine() { }
+        public CentroidLine() {}
 
+        /// <summary>
+        /// 
+        /// </summary>
+        public ICoordinate Centroid
+        {
+            get
+            {
+                ICoordinate cent = new Coordinate();
+                cent.X = centSum.X/totalLength;
+                cent.Y = centSum.Y/totalLength;
+                return cent;
+            }
+        }
+
         /// <summary> 
         /// Adds the linestring(s) defined by a Geometry to the centroid total.
         /// If the point is not linear it does not contribute to the centroid.
         /// </summary>
         /// <param name="geom">The point to add.</param>
         public void Add(IGeometry geom)
         {
-            if (geom is ILineString)             
-                Add(geom.Coordinates);            
+            if (geom is ILineString)
+            {
+                Add(geom.Coordinates);
+            }
 
-            else if (geom is IGeometryCollection) 
+            else if (geom is IGeometryCollection)
             {
                 IGeometryCollection gc = (IGeometryCollection) geom;
                 foreach (IGeometry geometry in gc.Geometries)
+                {
                     Add(geometry);
+                }
             }
         }
 
-        /// <summary>
-        /// 
-        /// </summary>
-        public ICoordinate Centroid
-        {
-            get
-            {
-                ICoordinate cent = new Coordinate();
-                cent.X = centSum.X / totalLength;
-                cent.Y = centSum.Y / totalLength;
-                return cent;
-            }
-        }
-
         /// <summary> 
         /// Adds the length defined by an array of coordinates.
         /// </summary>
@@ -62,11 +66,11 @@
                 double segmentLen = pts[i].Distance(pts[i + 1]);
                 totalLength += segmentLen;
 
-                double midx = (pts[i].X + pts[i + 1].X) / 2;
-                centSum.X += segmentLen * midx;
-                double midy = (pts[i].Y + pts[i + 1].Y) / 2;
-                centSum.Y += segmentLen * midy;
+                double midx = (pts[i].X + pts[i + 1].X)/2;
+                centSum.X += segmentLen*midx;
+                double midy = (pts[i].Y + pts[i + 1].Y)/2;
+                centSum.Y += segmentLen*midy;
             }
         }
     }
-}
+}
\ No newline at end of file