diff --git a/src/main/java/com/fanbin/KafkaMessageProducer.java b/src/main/java/com/fanbin/KafkaMessageProducer.java
index d4de14c..789ee80 100644
--- a/src/main/java/com/fanbin/KafkaMessageProducer.java
+++ b/src/main/java/com/fanbin/KafkaMessageProducer.java
@@ -6,7 +6,6 @@ import org.apache.kafka.clients.producer.ProducerRecord;
 import org.apache.kafka.common.serialization.StringSerializer;
 
 import java.util.Properties;
-import java.util.concurrent.TimeUnit;
 
 public class KafkaMessageProducer {
     private static final String TOPIC_NAME = "topic_100";
diff --git a/src/main/java/com/fanbin/MapPutTest.java b/src/main/java/com/fanbin/MapPutTest.java
index b965a8e..365325a 100644
--- a/src/main/java/com/fanbin/MapPutTest.java
+++ b/src/main/java/com/fanbin/MapPutTest.java
@@ -1,10 +1,6 @@
 package com.fanbin;
 
-import java.util.HashMap;
-import java.util.Map;
 import java.util.Random;
-import java.util.concurrent.CountDownLatch;
-import java.util.stream.IntStream;
 
 public class MapPutTest {
 
diff --git a/src/main/java/com/fanbin/SparkFileStreamingReader.java b/src/main/java/com/fanbin/SparkFileStreamingReader.java
index d379545..f44949e 100644
--- a/src/main/java/com/fanbin/SparkFileStreamingReader.java
+++ b/src/main/java/com/fanbin/SparkFileStreamingReader.java
@@ -1,7 +1,5 @@
 package com.fanbin;
 
-import java.util.concurrent.TimeoutException;
-
 import org.apache.spark.sql.Dataset;
 import org.apache.spark.sql.Row;
 import org.apache.spark.sql.SparkSession;
@@ -9,8 +7,8 @@ import org.apache.spark.sql.streaming.StreamingQuery;
 import org.apache.spark.sql.streaming.StreamingQueryException;
 import org.apache.spark.sql.types.DataTypes;
 import org.apache.spark.sql.types.StructType;
-import org.apache.spark.sql.types.DataTypes;
-import org.apache.spark.sql.types.StructType;
+
+import java.util.concurrent.TimeoutException;
 
 public class SparkFileStreamingReader {
     public static void main(String[] args) throws StreamingQueryException, TimeoutException {
diff --git a/src/main/java/com/fanbin/SparkKafkaReader.java b/src/main/java/com/fanbin/SparkKafkaReader.java
index de4c265..3a533bb 100644
--- a/src/main/java/com/fanbin/SparkKafkaReader.java
+++ b/src/main/java/com/fanbin/SparkKafkaReader.java
@@ -1,10 +1,5 @@
 package com.fanbin;
 
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.concurrent.TimeoutException;
-
 import com.codahale.metrics.MetricRegistry;
 import org.apache.spark.sql.Dataset;
 import org.apache.spark.sql.Row;
@@ -16,6 +11,8 @@ import org.apache.spark.sql.streaming.Trigger;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.concurrent.TimeoutException;
+
 public class SparkKafkaReader {
     private static final Logger logger = LoggerFactory.getLogger(SparkKafkaReader.class);
     private static final MetricRegistry metrics = new MetricRegistry();
diff --git a/src/main/java/com/fanbin/leetcode/ThreeNum.java b/src/main/java/com/fanbin/leetcode/ThreeNum.java
index 9e379d3..4b10fc8 100644
--- a/src/main/java/com/fanbin/leetcode/ThreeNum.java
+++ b/src/main/java/com/fanbin/leetcode/ThreeNum.java
@@ -1,9 +1,7 @@
 package com.fanbin.leetcode;
 
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 
 class ThreeNum {
     public List<List<Integer>> threeSum(int[] nums) {