diff --git a/checkstyle/checkstyle.xml b/checkstyle/checkstyle.xml
index 4b1db5e6219..fb2042b93e4 100644
--- a/checkstyle/checkstyle.xml
+++ b/checkstyle/checkstyle.xml
@@ -64,6 +64,7 @@
+
diff --git a/clients/src/main/java/org/apache/kafka/clients/producer/KafkaProducer.java b/clients/src/main/java/org/apache/kafka/clients/producer/KafkaProducer.java
index 2a75f9768bc..3fc2a1917e0 100644
--- a/clients/src/main/java/org/apache/kafka/clients/producer/KafkaProducer.java
+++ b/clients/src/main/java/org/apache/kafka/clients/producer/KafkaProducer.java
@@ -13,7 +13,11 @@
package org.apache.kafka.clients.producer;
import java.net.InetSocketAddress;
-import java.util.*;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
diff --git a/clients/src/main/java/org/apache/kafka/clients/producer/MockProducer.java b/clients/src/main/java/org/apache/kafka/clients/producer/MockProducer.java
index 36e7ffa2a0a..8388ab89efb 100644
--- a/clients/src/main/java/org/apache/kafka/clients/producer/MockProducer.java
+++ b/clients/src/main/java/org/apache/kafka/clients/producer/MockProducer.java
@@ -29,7 +29,11 @@ import java.util.concurrent.TimeUnit;
import org.apache.kafka.clients.producer.internals.FutureRecordMetadata;
import org.apache.kafka.clients.producer.internals.DefaultPartitioner;
import org.apache.kafka.clients.producer.internals.ProduceRequestResult;
-import org.apache.kafka.common.*;
+import org.apache.kafka.common.Cluster;
+import org.apache.kafka.common.Metric;
+import org.apache.kafka.common.MetricName;
+import org.apache.kafka.common.PartitionInfo;
+import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.serialization.Serializer;
diff --git a/clients/src/main/java/org/apache/kafka/common/Cluster.java b/clients/src/main/java/org/apache/kafka/common/Cluster.java
index c7f3e075a53..8883e456024 100644
--- a/clients/src/main/java/org/apache/kafka/common/Cluster.java
+++ b/clients/src/main/java/org/apache/kafka/common/Cluster.java
@@ -15,7 +15,13 @@ package org.apache.kafka.common;
import org.apache.kafka.common.utils.Utils;
import java.net.InetSocketAddress;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
/**
* A representation of a subset of the nodes, topics, and partitions in the Kafka cluster.
diff --git a/clients/src/main/java/org/apache/kafka/common/config/AbstractConfig.java b/clients/src/main/java/org/apache/kafka/common/config/AbstractConfig.java
index afb3b3f1fd5..f9b6cdfaf19 100644
--- a/clients/src/main/java/org/apache/kafka/common/config/AbstractConfig.java
+++ b/clients/src/main/java/org/apache/kafka/common/config/AbstractConfig.java
@@ -12,7 +12,13 @@
*/
package org.apache.kafka.common.config;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
import org.apache.kafka.common.Configurable;
import org.apache.kafka.common.KafkaException;
diff --git a/clients/src/main/java/org/apache/kafka/common/network/Selector.java b/clients/src/main/java/org/apache/kafka/common/network/Selector.java
index 3f29f15a8df..8bb33488cb2 100644
--- a/clients/src/main/java/org/apache/kafka/common/network/Selector.java
+++ b/clients/src/main/java/org/apache/kafka/common/network/Selector.java
@@ -15,8 +15,20 @@ package org.apache.kafka.common.network;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;
-import java.nio.channels.*;
-import java.util.*;
+import java.nio.channels.CancelledKeyException;
+import java.nio.channels.ClosedChannelException;
+import java.nio.channels.SelectionKey;
+import java.nio.channels.SocketChannel;
+import java.nio.channels.UnresolvedAddressException;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
import java.util.concurrent.TimeUnit;
import org.apache.kafka.common.KafkaException;
diff --git a/clients/src/main/java/org/apache/kafka/common/protocol/Errors.java b/clients/src/main/java/org/apache/kafka/common/protocol/Errors.java
index dd4f39c4ead..ad0de2f2faa 100644
--- a/clients/src/main/java/org/apache/kafka/common/protocol/Errors.java
+++ b/clients/src/main/java/org/apache/kafka/common/protocol/Errors.java
@@ -19,8 +19,30 @@ package org.apache.kafka.common.protocol;
import java.util.HashMap;
import java.util.Map;
-import org.apache.kafka.common.errors.*;
+import org.apache.kafka.common.errors.ApiException;
+import org.apache.kafka.common.errors.AuthorizationException;
+import org.apache.kafka.common.errors.BrokerNotAvailableException;
import org.apache.kafka.common.errors.ControllerMovedException;
+import org.apache.kafka.common.errors.CorruptRecordException;
+import org.apache.kafka.common.errors.GroupCoordinatorNotAvailableException;
+import org.apache.kafka.common.errors.GroupLoadInProgressException;
+import org.apache.kafka.common.errors.IllegalGenerationException;
+import org.apache.kafka.common.errors.InvalidRequiredAcksException;
+import org.apache.kafka.common.errors.InvalidTopicException;
+import org.apache.kafka.common.errors.LeaderNotAvailableException;
+import org.apache.kafka.common.errors.NetworkException;
+import org.apache.kafka.common.errors.NotCoordinatorForGroupException;
+import org.apache.kafka.common.errors.NotEnoughReplicasAfterAppendException;
+import org.apache.kafka.common.errors.NotEnoughReplicasException;
+import org.apache.kafka.common.errors.NotLeaderForPartitionException;
+import org.apache.kafka.common.errors.OffsetMetadataTooLarge;
+import org.apache.kafka.common.errors.RebalanceInProgressException;
+import org.apache.kafka.common.errors.RecordBatchTooLargeException;
+import org.apache.kafka.common.errors.RecordTooLargeException;
+import org.apache.kafka.common.errors.TimeoutException;
+import org.apache.kafka.common.errors.UnknownMemberIdException;
+import org.apache.kafka.common.errors.UnknownServerException;
+import org.apache.kafka.common.errors.UnknownTopicOrPartitionException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
diff --git a/clients/src/main/java/org/apache/kafka/common/requests/ControlledShutdownResponse.java b/clients/src/main/java/org/apache/kafka/common/requests/ControlledShutdownResponse.java
index add3fa67ee5..862264fbf7c 100644
--- a/clients/src/main/java/org/apache/kafka/common/requests/ControlledShutdownResponse.java
+++ b/clients/src/main/java/org/apache/kafka/common/requests/ControlledShutdownResponse.java
@@ -19,7 +19,10 @@ import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
public class ControlledShutdownResponse extends AbstractRequestResponse {
diff --git a/clients/src/main/java/org/apache/kafka/common/requests/LeaderAndIsrRequest.java b/clients/src/main/java/org/apache/kafka/common/requests/LeaderAndIsrRequest.java
index 9932fbb32ab..a77a7cbd628 100644
--- a/clients/src/main/java/org/apache/kafka/common/requests/LeaderAndIsrRequest.java
+++ b/clients/src/main/java/org/apache/kafka/common/requests/LeaderAndIsrRequest.java
@@ -25,7 +25,12 @@ import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
public class LeaderAndIsrRequest extends AbstractRequest {
diff --git a/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaRequest.java b/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaRequest.java
index 11c2b7564d4..80223a17bc1 100644
--- a/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaRequest.java
+++ b/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaRequest.java
@@ -21,7 +21,12 @@ import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
public class StopReplicaRequest extends AbstractRequest {
private static final Schema CURRENT_SCHEMA = ProtoUtils.currentRequestSchema(ApiKeys.STOP_REPLICA.id);
diff --git a/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaResponse.java b/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaResponse.java
index a8e736cfa8a..3c4db681b83 100644
--- a/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaResponse.java
+++ b/clients/src/main/java/org/apache/kafka/common/requests/StopReplicaResponse.java
@@ -21,7 +21,10 @@ import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
public class StopReplicaResponse extends AbstractRequestResponse {
private static final Schema CURRENT_SCHEMA = ProtoUtils.currentResponseSchema(ApiKeys.STOP_REPLICA.id);
diff --git a/clients/src/main/java/org/apache/kafka/common/requests/UpdateMetadataRequest.java b/clients/src/main/java/org/apache/kafka/common/requests/UpdateMetadataRequest.java
index 4c65ce9c3ce..808161c65dc 100644
--- a/clients/src/main/java/org/apache/kafka/common/requests/UpdateMetadataRequest.java
+++ b/clients/src/main/java/org/apache/kafka/common/requests/UpdateMetadataRequest.java
@@ -22,7 +22,13 @@ import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
public class UpdateMetadataRequest extends AbstractRequest {
diff --git a/clients/src/main/java/org/apache/kafka/common/security/ssl/SslFactory.java b/clients/src/main/java/org/apache/kafka/common/security/ssl/SslFactory.java
index a7cf9a20c3f..cb14c64d707 100644
--- a/clients/src/main/java/org/apache/kafka/common/security/ssl/SslFactory.java
+++ b/clients/src/main/java/org/apache/kafka/common/security/ssl/SslFactory.java
@@ -22,15 +22,20 @@ import org.apache.kafka.common.config.SslConfigs;
import org.apache.kafka.common.network.Mode;
import org.apache.kafka.common.config.types.Password;
-import javax.net.ssl.*;
import java.io.FileInputStream;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.KeyStore;
-
import java.util.List;
import java.util.Map;
+import javax.net.ssl.KeyManager;
+import javax.net.ssl.KeyManagerFactory;
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.SSLEngine;
+import javax.net.ssl.SSLParameters;
+import javax.net.ssl.TrustManagerFactory;
+
public class SslFactory implements Configurable {
private String protocol;
diff --git a/clients/src/test/java/org/apache/kafka/clients/MetadataTest.java b/clients/src/test/java/org/apache/kafka/clients/MetadataTest.java
index bd3bbe80589..0493eb25e03 100644
--- a/clients/src/test/java/org/apache/kafka/clients/MetadataTest.java
+++ b/clients/src/test/java/org/apache/kafka/clients/MetadataTest.java
@@ -27,7 +27,12 @@ import org.apache.kafka.test.TestUtils;
import org.junit.After;
import org.junit.Test;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
public class MetadataTest {
diff --git a/clients/src/test/java/org/apache/kafka/clients/producer/internals/BufferPoolTest.java b/clients/src/test/java/org/apache/kafka/clients/producer/internals/BufferPoolTest.java
index b103bee294d..72d85a2328a 100644
--- a/clients/src/test/java/org/apache/kafka/clients/producer/internals/BufferPoolTest.java
+++ b/clients/src/test/java/org/apache/kafka/clients/producer/internals/BufferPoolTest.java
@@ -29,7 +29,9 @@ import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assert.assertEquals;
public class BufferPoolTest {
private MockTime time = new MockTime();
diff --git a/clients/src/test/java/org/apache/kafka/common/network/SelectorTest.java b/clients/src/test/java/org/apache/kafka/common/network/SelectorTest.java
index 0e5db8cd223..4d3b1c8d967 100644
--- a/clients/src/test/java/org/apache/kafka/common/network/SelectorTest.java
+++ b/clients/src/test/java/org/apache/kafka/common/network/SelectorTest.java
@@ -21,7 +21,6 @@ import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.nio.ByteBuffer;
-import java.util.*;
import org.apache.kafka.common.metrics.Metrics;
import org.apache.kafka.common.utils.MockTime;
diff --git a/clients/src/test/java/org/apache/kafka/common/record/MemoryRecordsTest.java b/clients/src/test/java/org/apache/kafka/common/record/MemoryRecordsTest.java
index e343327faf1..6e3a9ac5ad1 100644
--- a/clients/src/test/java/org/apache/kafka/common/record/MemoryRecordsTest.java
+++ b/clients/src/test/java/org/apache/kafka/common/record/MemoryRecordsTest.java
@@ -22,7 +22,11 @@ import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
diff --git a/clients/src/test/java/org/apache/kafka/common/security/ssl/SslFactoryTest.java b/clients/src/test/java/org/apache/kafka/common/security/ssl/SslFactoryTest.java
index b5710aa1b61..5336db7c18a 100644
--- a/clients/src/test/java/org/apache/kafka/common/security/ssl/SslFactoryTest.java
+++ b/clients/src/test/java/org/apache/kafka/common/security/ssl/SslFactoryTest.java
@@ -12,15 +12,15 @@
*/
package org.apache.kafka.common.security.ssl;
-import javax.net.ssl.*;
-
import java.io.File;
import java.util.Map;
+import javax.net.ssl.SSLEngine;
+
import org.apache.kafka.test.TestSslUtils;
import org.apache.kafka.common.network.Mode;
-
import org.junit.Test;
+
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertArrayEquals;
diff --git a/clients/src/test/java/org/apache/kafka/common/utils/AbstractIteratorTest.java b/clients/src/test/java/org/apache/kafka/common/utils/AbstractIteratorTest.java
index c788e66035b..3f41084f3ba 100644
--- a/clients/src/test/java/org/apache/kafka/common/utils/AbstractIteratorTest.java
+++ b/clients/src/test/java/org/apache/kafka/common/utils/AbstractIteratorTest.java
@@ -20,7 +20,11 @@ import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.NoSuchElementException;
import org.junit.Test;
diff --git a/clients/src/test/java/org/apache/kafka/common/utils/UtilsTest.java b/clients/src/test/java/org/apache/kafka/common/utils/UtilsTest.java
index 74ec52bc521..04dc3d2ab31 100755
--- a/clients/src/test/java/org/apache/kafka/common/utils/UtilsTest.java
+++ b/clients/src/test/java/org/apache/kafka/common/utils/UtilsTest.java
@@ -25,7 +25,7 @@ import org.junit.Test;
import static org.apache.kafka.common.utils.Utils.getHost;
import static org.apache.kafka.common.utils.Utils.getPort;
import static org.apache.kafka.common.utils.Utils.formatAddress;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
public class UtilsTest {
diff --git a/clients/src/test/java/org/apache/kafka/test/TestSslUtils.java b/clients/src/test/java/org/apache/kafka/test/TestSslUtils.java
index b92a06d793b..c3895027c31 100644
--- a/clients/src/test/java/org/apache/kafka/test/TestSslUtils.java
+++ b/clients/src/test/java/org/apache/kafka/test/TestSslUtils.java
@@ -27,8 +27,17 @@ import java.io.FileInputStream;
import java.io.IOException;
import java.io.EOFException;
import java.math.BigInteger;
+
import javax.net.ssl.TrustManagerFactory;
-import java.security.*;
+
+import java.security.GeneralSecurityException;
+import java.security.Key;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.KeyStore;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.security.Security;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
diff --git a/connect/api/src/main/java/org/apache/kafka/connect/data/ConnectSchema.java b/connect/api/src/main/java/org/apache/kafka/connect/data/ConnectSchema.java
index c73dafc3637..37c056a6928 100644
--- a/connect/api/src/main/java/org/apache/kafka/connect/data/ConnectSchema.java
+++ b/connect/api/src/main/java/org/apache/kafka/connect/data/ConnectSchema.java
@@ -21,7 +21,11 @@ import org.apache.kafka.connect.errors.DataException;
import java.math.BigDecimal;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
public class ConnectSchema implements Schema {
/**
diff --git a/connect/file/src/main/java/org/apache/kafka/connect/file/FileStreamSourceTask.java b/connect/file/src/main/java/org/apache/kafka/connect/file/FileStreamSourceTask.java
index f30b603d1f7..af50d4d7bf2 100644
--- a/connect/file/src/main/java/org/apache/kafka/connect/file/FileStreamSourceTask.java
+++ b/connect/file/src/main/java/org/apache/kafka/connect/file/FileStreamSourceTask.java
@@ -17,6 +17,17 @@
package org.apache.kafka.connect.file;
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+
import org.apache.kafka.connect.data.Schema;
import org.apache.kafka.connect.errors.ConnectException;
import org.apache.kafka.connect.source.SourceRecord;
@@ -24,9 +35,6 @@ import org.apache.kafka.connect.source.SourceTask;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-import java.io.*;
-import java.util.*;
-
/**
* FileStreamSourceTask reads from stdin or a file.
*/
diff --git a/connect/json/src/main/java/org/apache/kafka/connect/json/JsonConverter.java b/connect/json/src/main/java/org/apache/kafka/connect/json/JsonConverter.java
index 815d32b00b7..ed295e19902 100644
--- a/connect/json/src/main/java/org/apache/kafka/connect/json/JsonConverter.java
+++ b/connect/json/src/main/java/org/apache/kafka/connect/json/JsonConverter.java
@@ -25,7 +25,16 @@ import org.apache.kafka.common.cache.Cache;
import org.apache.kafka.common.cache.LRUCache;
import org.apache.kafka.common.cache.SynchronizedCache;
import org.apache.kafka.common.errors.SerializationException;
-import org.apache.kafka.connect.data.*;
+import org.apache.kafka.connect.data.SchemaBuilder;
+import org.apache.kafka.connect.data.Schema;
+import org.apache.kafka.connect.data.Struct;
+import org.apache.kafka.connect.data.Field;
+import org.apache.kafka.connect.data.ConnectSchema;
+import org.apache.kafka.connect.data.SchemaAndValue;
+import org.apache.kafka.connect.data.Timestamp;
+import org.apache.kafka.connect.data.Time;
+import org.apache.kafka.connect.data.Decimal;
+import org.apache.kafka.connect.data.Date;
import org.apache.kafka.connect.errors.DataException;
import org.apache.kafka.connect.storage.Converter;
diff --git a/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/Worker.java b/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/Worker.java
index f5b23ecda6b..3898ad60aac 100644
--- a/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/Worker.java
+++ b/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/Worker.java
@@ -29,7 +29,11 @@ import org.apache.kafka.connect.connector.Task;
import org.apache.kafka.connect.errors.ConnectException;
import org.apache.kafka.connect.sink.SinkTask;
import org.apache.kafka.connect.source.SourceTask;
-import org.apache.kafka.connect.storage.*;
+import org.apache.kafka.connect.storage.Converter;
+import org.apache.kafka.connect.storage.OffsetBackingStore;
+import org.apache.kafka.connect.storage.OffsetStorageReader;
+import org.apache.kafka.connect.storage.OffsetStorageWriter;
+import org.apache.kafka.connect.storage.OffsetStorageReaderImpl;
import org.apache.kafka.connect.util.ConnectorTaskId;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
diff --git a/connect/runtime/src/main/java/org/apache/kafka/connect/storage/FileOffsetBackingStore.java b/connect/runtime/src/main/java/org/apache/kafka/connect/storage/FileOffsetBackingStore.java
index 1d1f8ef4bd9..1032bced8ff 100644
--- a/connect/runtime/src/main/java/org/apache/kafka/connect/storage/FileOffsetBackingStore.java
+++ b/connect/runtime/src/main/java/org/apache/kafka/connect/storage/FileOffsetBackingStore.java
@@ -21,7 +21,14 @@ import org.apache.kafka.connect.errors.ConnectException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-import java.io.*;
+import java.io.EOFException;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.Map;
diff --git a/connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageWriter.java b/connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageWriter.java
index 58376e5497b..3d1e70b21f9 100644
--- a/connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageWriter.java
+++ b/connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageWriter.java
@@ -23,7 +23,9 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.nio.ByteBuffer;
-import java.util.*;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
import java.util.concurrent.Future;
/**
diff --git a/connect/runtime/src/test/java/org/apache/kafka/connect/runtime/WorkerSourceTaskTest.java b/connect/runtime/src/test/java/org/apache/kafka/connect/runtime/WorkerSourceTaskTest.java
index 7380f1c63e9..f16cbebb64e 100644
--- a/connect/runtime/src/test/java/org/apache/kafka/connect/runtime/WorkerSourceTaskTest.java
+++ b/connect/runtime/src/test/java/org/apache/kafka/connect/runtime/WorkerSourceTaskTest.java
@@ -45,13 +45,21 @@ import org.powermock.api.easymock.annotation.Mock;
import org.powermock.modules.junit4.PowerMockRunner;
import org.powermock.reflect.Whitebox;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertNull;
@RunWith(PowerMockRunner.class)
public class WorkerSourceTaskTest extends ThreadedTest {
diff --git a/connect/runtime/src/test/java/org/apache/kafka/connect/storage/OffsetStorageWriterTest.java b/connect/runtime/src/test/java/org/apache/kafka/connect/storage/OffsetStorageWriterTest.java
index 3e0347c3cf4..3f7082fc876 100644
--- a/connect/runtime/src/test/java/org/apache/kafka/connect/storage/OffsetStorageWriterTest.java
+++ b/connect/runtime/src/test/java/org/apache/kafka/connect/storage/OffsetStorageWriterTest.java
@@ -35,7 +35,12 @@ import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Map;
-import java.util.concurrent.*;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.Callable;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
diff --git a/tools/src/main/java/org/apache/kafka/tools/ProducerPerformance.java b/tools/src/main/java/org/apache/kafka/tools/ProducerPerformance.java
index 3a068626c5c..18daf09b62d 100644
--- a/tools/src/main/java/org/apache/kafka/tools/ProducerPerformance.java
+++ b/tools/src/main/java/org/apache/kafka/tools/ProducerPerformance.java
@@ -18,13 +18,17 @@ import java.util.Arrays;
import java.util.List;
import java.util.Properties;
+import org.apache.kafka.clients.producer.Callback;
+import org.apache.kafka.clients.producer.KafkaProducer;
+import org.apache.kafka.clients.producer.ProducerConfig;
+import org.apache.kafka.clients.producer.ProducerRecord;
+import org.apache.kafka.clients.producer.RecordMetadata;
+
import net.sourceforge.argparse4j.ArgumentParsers;
import net.sourceforge.argparse4j.inf.ArgumentParser;
import net.sourceforge.argparse4j.inf.ArgumentParserException;
import net.sourceforge.argparse4j.inf.Namespace;
-import org.apache.kafka.clients.producer.*;
-
public class ProducerPerformance {
public static void main(String[] args) throws Exception {