diff --git a/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImpl.java b/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImpl.java
index 15686dd0..8514c0ed 100644
--- a/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImpl.java
+++ b/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImpl.java
@@ -42,6 +42,11 @@ class JobNeighborhoodsImpl implements JobNeighborhoods {
             public Job next() {
                 return null;
             }
+
+            @Override
+            public void remove() {
+
+            }
         };
         Iterator<ReferencedJob> descendingIterator = tree.iterator();
         return new NearestNeighborhoodIterator(descendingIterator, nNeighbors);
diff --git a/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImplWithCapRestriction.java b/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImplWithCapRestriction.java
index b3d507db..789d1bf3 100644
--- a/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImplWithCapRestriction.java
+++ b/jsprit-core/src/main/java/jsprit/core/algorithm/ruin/JobNeighborhoodsImplWithCapRestriction.java
@@ -47,6 +47,11 @@ class JobNeighborhoodsImplWithCapRestriction implements JobNeighborhoods {
                 return null;
             }
 
+            @Override
+            public void remove() {
+
+            }
+
         };
         Iterator<ReferencedJob> descendingIterator = tree.iterator();
         return new NearestNeighborhoodIterator(descendingIterator, nNeighbors);