diff --git a/processing/src/main/java/io/druid/query/lookup/LookupSnapshotTaker.java b/processing/src/main/java/io/druid/query/lookup/LookupSnapshotTaker.java
index f49f4b7c120..bf9131452b7 100644
--- a/processing/src/main/java/io/druid/query/lookup/LookupSnapshotTaker.java
+++ b/processing/src/main/java/io/druid/query/lookup/LookupSnapshotTaker.java
@@ -37,7 +37,7 @@ import java.util.List;
 public class LookupSnapshotTaker
 {
   private static final Logger LOGGER = new Logger(LookupSnapshotTaker.class);
-  private static final String PERSIST_FILE_NAME = "lookupSnapshot.json";
+  protected static final String PERSIST_FILE_NAME = "lookupSnapshot.json";
 
   private final ObjectMapper objectMapper;
   private final File persistDirectory;
diff --git a/processing/src/test/java/io/druid/query/lookup/LookupSnapshotTakerTest.java b/processing/src/test/java/io/druid/query/lookup/LookupSnapshotTakerTest.java
index b4e3df29671..08e7d9d6d61 100644
--- a/processing/src/test/java/io/druid/query/lookup/LookupSnapshotTakerTest.java
+++ b/processing/src/test/java/io/druid/query/lookup/LookupSnapshotTakerTest.java
@@ -73,7 +73,10 @@ public class LookupSnapshotTakerTest
   public void testIOExceptionDuringLookupPersist() throws IOException
   {
     File directory = temporaryFolder.newFolder();
-    directory.setReadOnly();
+    File snapshotFile = new File(directory, LookupSnapshotTaker.PERSIST_FILE_NAME);
+    Assert.assertFalse(snapshotFile.exists());
+    Assert.assertTrue(snapshotFile.createNewFile());
+    Assert.assertTrue(snapshotFile.setReadOnly());
     LookupSnapshotTaker lookupSnapshotTaker = new LookupSnapshotTaker(mapper, directory.getAbsolutePath());
     LookupBean lookupBean = new LookupBean();
     lookupBean.name = "name";