diff --git a/zeppelin-zengine/src/main/java/org/apache/zeppelin/notebook/Notebook.java b/zeppelin-zengine/src/main/java/org/apache/zeppelin/notebook/Notebook.java
index 77fe78f097..823d8e50bc 100644
--- a/zeppelin-zengine/src/main/java/org/apache/zeppelin/notebook/Notebook.java
+++ b/zeppelin-zengine/src/main/java/org/apache/zeppelin/notebook/Notebook.java
@@ -20,7 +20,6 @@ package org.apache.zeppelin.notebook;
 import java.io.IOException;
 import java.io.StringReader;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
@@ -34,12 +33,10 @@ import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import com.google.common.base.Predicate;
 import com.google.common.collect.FluentIterable;
-import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.stream.JsonReader;
-import org.apache.commons.codec.binary.StringUtils;
 import org.quartz.CronScheduleBuilder;
 import org.quartz.CronTrigger;
 import org.quartz.JobBuilder;