diff --git a/src/main/java/io/anserini/ltr/feature/base/StopCover.java b/src/main/java/io/anserini/ltr/feature/base/StopCover.java
index 5071a16e28..cea54d2158 100644
--- a/src/main/java/io/anserini/ltr/feature/base/StopCover.java
+++ b/src/main/java/io/anserini/ltr/feature/base/StopCover.java
@@ -17,7 +17,7 @@
 package io.anserini.ltr.feature.base;
 
 import io.anserini.index.IndexArgs;
-import io.anserini.ltr.StopWords;
+import io.anserini.ltr.Stopwords;
 import io.anserini.ltr.feature.*;
 
 import java.util.List;
@@ -43,7 +43,7 @@ public float extract(DocumentContext documentContext, QueryContext queryContext)
         DocumentFieldContext context = documentContext.fieldContexts.get(field);
         long cov = 0l;
         float score = 0.0f;
-        List<String> stopWords = StopWords.getStopWordList();
+        List<String> stopWords = Stopwords.getStopWordList();
         for (String stopWord : stopWords) {
             if (context.termFreqs.containsKey(stopWord)) {
                     cov += context.termFreqs.get(stopWord);
diff --git a/src/main/java/io/anserini/ltr/feature/base/StopRatio.java b/src/main/java/io/anserini/ltr/feature/base/StopRatio.java
index a29f44a816..cff5dfa0b1 100644
--- a/src/main/java/io/anserini/ltr/feature/base/StopRatio.java
+++ b/src/main/java/io/anserini/ltr/feature/base/StopRatio.java
@@ -17,7 +17,7 @@
 package io.anserini.ltr.feature.base;
 
 import io.anserini.index.IndexArgs;
-import io.anserini.ltr.StopWords;
+import io.anserini.ltr.Stopwords;
 import io.anserini.ltr.feature.*;
 
 import java.util.List;
@@ -43,7 +43,7 @@ public float extract(DocumentContext documentContext, QueryContext queryContext)
         DocumentFieldContext context = documentContext.fieldContexts.get(field);
         long cov = 0l;
         float score = 0.0f;
-        List<String> stopWords = StopWords.getStopWordList();
+        List<String> stopWords = Stopwords.getStopWordList();
         for (String stopWord : stopWords) {
             if (context.termFreqs.containsKey(stopWord)) {
                 cov += context.termFreqs.get(stopWord);
diff --git a/tools b/tools
index e4bd123490..4e2c9f0658 160000
--- a/tools
+++ b/tools
@@ -1 +1 @@
-Subproject commit e4bd12349000a084a8ae285528fb6c1607639c12
+Subproject commit 4e2c9f065895ecd0a1ec707b25bb07deb649047e