Add spotless maven plugin to enforce java format. (#6782)

Add a spotless maven plugin to enforce java format.
If java file is not formatted properly, the build will failed and hint developer to run `mvn spotless:apply` to fix the violation.

Two basic rules added:
- Default import order
- Remove unused imports

pinot-broker/src/main/java/org/apache/pinot/broker/api/HttpRequesterIdentity.java

@@ -19,7 +19,6 @@
 package org.apache.pinot.broker.api;
 
 import com.google.common.collect.Multimap;
-import java.security.Principal;
 
 
 /**

pinot-broker/src/main/java/org/apache/pinot/broker/routing/segmentpruner/SegmentPrunerFactory.java

@@ -19,7 +19,6 @@
 package org.apache.pinot.broker.routing.segmentpruner;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import javax.annotation.Nullable;

pinot-broker/src/test/java/org/apache/pinot/broker/broker/BasicAuthAccessControlTest.java

@@ -20,6 +20,8 @@
 
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.Multimap;
+import java.util.HashMap;
+import java.util.Map;
 import org.apache.pinot.broker.api.AccessControl;
 import org.apache.pinot.broker.api.HttpRequesterIdentity;
 import org.apache.pinot.common.request.BrokerRequest;
@@ -28,8 +30,6 @@
 import org.testng.Assert;
 import org.testng.annotations.BeforeClass;
 import org.testng.annotations.Test;
-import java.util.HashMap;
-import java.util.Map;
 
 
 public class BasicAuthAccessControlTest {

pinot-clients/pinot-java-client/src/main/java/org/apache/pinot/client/JsonAsyncHttpPinotClientTransport.java

@@ -24,7 +24,6 @@
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.ning.http.client.AsyncHttpClient;
 import com.ning.http.client.Response;
-
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/AggregationResultSetTest.java

@@ -18,14 +18,13 @@
  */
 package org.apache.pinot.client;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertNotEquals;
-
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
 
 public class AggregationResultSetTest {
 

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/ConnectionFactoryTest.java

@@ -22,7 +22,6 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-
 import org.testng.Assert;
 import org.testng.annotations.Test;
 

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/DynamicBrokerSelectorTest.java

@@ -18,23 +18,22 @@
  */
 package org.apache.pinot.client;
 
-import static org.mockito.Mockito.times;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.when;
-import static org.mockito.MockitoAnnotations.initMocks;
-import static org.testng.Assert.assertEquals;
-
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-
 import org.I0Itec.zkclient.ZkClient;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.mockito.MockitoAnnotations.initMocks;
+import static org.testng.Assert.assertEquals;
+
 public class DynamicBrokerSelectorTest {
 
   @Mock

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/ExecutionStatsTest.java

@@ -18,17 +18,16 @@
  */
 package org.apache.pinot.client;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.Test;
+
 import static org.testng.Assert.assertEquals;
 import static org.testng.Assert.assertNotEquals;
 import static org.testng.Assert.assertNotNull;
 import static org.testng.Assert.assertTrue;
 
-import org.testng.annotations.BeforeMethod;
-import org.testng.annotations.Test;
-
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
-
 public class ExecutionStatsTest {
 
   private JsonNode mockBrokerResponse;

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/ExternalViewReaderTest.java

@@ -18,25 +18,24 @@
  */
 package org.apache.pinot.client;
 
-import static org.mockito.Mockito.when;
-import static org.mockito.MockitoAnnotations.initMocks;
-import static org.testng.Assert.assertEquals;
-
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-
 import org.I0Itec.zkclient.ZkClient;
 import org.apache.commons.io.IOUtils;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
+import static org.mockito.Mockito.when;
+import static org.mockito.MockitoAnnotations.initMocks;
+import static org.testng.Assert.assertEquals;
+
 public class ExternalViewReaderTest {
 
   @Mock

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/GroupByResultSetTest.java

@@ -18,14 +18,13 @@
  */
 package org.apache.pinot.client;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertNotEquals;
-
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
 
 public class GroupByResultSetTest {
 

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/ResultTableResultSetTest.java

@@ -18,17 +18,15 @@
  */
 package org.apache.pinot.client;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertNotEquals;
-import static org.testng.Assert.assertNotNull;
-
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import java.util.List;
-
 import org.testng.annotations.BeforeTest;
 import org.testng.annotations.Test;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
+import static org.testng.Assert.assertNotNull;
 
 public class ResultTableResultSetTest {
 

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/SelectionResultSetTest.java

@@ -18,14 +18,13 @@
  */
 package org.apache.pinot.client;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertNotEquals;
-
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
 
 public class SelectionResultSetTest {
 

pinot-clients/pinot-java-client/src/test/java/org/apache/pinot/client/TextTableTest.java

@@ -18,12 +18,12 @@
  */
 package org.apache.pinot.client;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertNotEquals;
-
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
+
 public class TextTableTest {
 
   private TextTable textTableUnderTest;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/PinotConnectionMetaData.java

@@ -20,7 +20,6 @@
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
-
 import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.SQLException;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/PinotDriver.java

@@ -18,7 +18,6 @@
  */
 package org.apache.pinot.client;
 
-import com.google.common.base.Preconditions;
 import com.google.common.collect.Iterables;
 import java.net.URI;
 import java.sql.Connection;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/PinotResultSet.java

@@ -39,7 +39,6 @@
 import org.apache.commons.codec.binary.Hex;
 import org.apache.pinot.client.base.AbstractBaseResultSet;
 import org.apache.pinot.client.utils.DateTimeUtils;
-import org.apache.pinot.client.utils.DriverUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/base/AbstractBaseConnection.java

@@ -23,7 +23,6 @@
 import java.sql.CallableStatement;
 import java.sql.Clob;
 import java.sql.Connection;
-import java.sql.DatabaseMetaData;
 import java.sql.NClob;
 import java.sql.PreparedStatement;
 import java.sql.SQLClientInfoException;
@@ -37,7 +36,6 @@
 import java.util.Map;
 import java.util.Properties;
 import java.util.concurrent.Executor;
-import org.apache.pinot.client.PinotConnectionMetaData;
 
 
 public abstract class AbstractBaseConnection implements Connection {

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/base/AbstractBaseResultSet.java

@@ -29,7 +29,6 @@
 import java.sql.NClob;
 import java.sql.Ref;
 import java.sql.ResultSet;
-import java.sql.ResultSetMetaData;
 import java.sql.RowId;
 import java.sql.SQLException;
 import java.sql.SQLFeatureNotSupportedException;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/base/AbstractBaseResultSetMetadata.java

@@ -19,9 +19,7 @@
 package org.apache.pinot.client.base;
 
 import java.sql.ResultSetMetaData;
-import java.sql.SQLData;
 import java.sql.SQLException;
-import java.sql.Types;
 import org.apache.pinot.client.utils.Constants;
 
 

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/controller/PinotControllerTransport.java

@@ -20,11 +20,9 @@
 
 import com.ning.http.client.AsyncHttpClient;
 import com.ning.http.client.Response;
-
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
-
 import org.apache.pinot.client.PinotClientException;
 import org.apache.pinot.client.controller.response.ControllerTenantBrokerResponse;
 import org.apache.pinot.client.controller.response.SchemaResponse;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/controller/response/ControllerTenantBrokerResponse.java

@@ -21,9 +21,7 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectReader;
-import com.google.common.collect.Lists;
 import com.ning.http.client.Response;
-
 import java.io.IOException;
 import java.util.*;
 import java.util.concurrent.ExecutionException;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/controller/response/SchemaResponse.java

@@ -23,8 +23,6 @@
 import com.fasterxml.jackson.databind.ObjectReader;
 import com.ning.http.client.Response;
 import java.io.IOException;
-import java.util.List;
-import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;

pinot-clients/pinot-jdbc-client/src/main/java/org/apache/pinot/client/utils/DriverUtils.java

@@ -18,10 +18,8 @@
  */
 package org.apache.pinot.client.utils;
 
-import com.ning.http.client.uri.Uri;
 import java.net.URI;
 import java.sql.Types;
-import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import org.slf4j.Logger;

pinot-clients/pinot-jdbc-client/src/test/java/org/apache/pinot/client/DummyPinotClientTransport.java

@@ -62,4 +62,3 @@ public void close()
 
   }
 }
-

pinot-clients/pinot-jdbc-client/src/test/java/org/apache/pinot/client/PinotConnectionTest.java

@@ -19,7 +19,6 @@
 package org.apache.pinot.client;
 
 import java.sql.Statement;
-import java.util.Collections;
 import org.testng.Assert;
 import org.testng.annotations.AfterClass;
 import org.testng.annotations.BeforeClass;

pinot-clients/pinot-jdbc-client/src/test/java/org/apache/pinot/client/PinotDriverTest.java

@@ -18,8 +18,6 @@
  */
 package org.apache.pinot.client;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.ResultSet;

pinot-clients/pinot-jdbc-client/src/test/java/org/apache/pinot/client/PinotPreparedStatementTest.java

@@ -23,7 +23,6 @@
 import java.sql.PreparedStatement;
 import java.sql.Time;
 import java.sql.Timestamp;
-import java.util.Collections;
 import org.apache.commons.codec.binary.Hex;
 import org.apache.pinot.client.utils.DateTimeUtils;
 import org.testng.Assert;

pinot-clients/pinot-jdbc-client/src/test/java/org/apache/pinot/client/PinotStatementTest.java

@@ -20,8 +20,6 @@
 
 import java.sql.ResultSet;
 import java.sql.Statement;
-import java.util.Collections;
-import java.util.concurrent.Future;
 import org.testng.Assert;
 import org.testng.annotations.AfterClass;
 import org.testng.annotations.BeforeClass;

pinot-common/src/main/java/org/apache/pinot/common/request/AggregationInfo.java

@@ -808,4 +808,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-

pinot-common/src/main/java/org/apache/pinot/common/request/BrokerRequest.java

@@ -2549,4 +2549,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-

pinot-common/src/main/java/org/apache/pinot/common/request/DataSource.java

@@ -387,4 +387,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-

pinot-common/src/main/java/org/apache/pinot/common/request/Expression.java

@@ -723,4 +723,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-

pinot-common/src/main/java/org/apache/pinot/common/request/FilterQuery.java

@@ -928,4 +928,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-

pinot-common/src/main/java/org/apache/pinot/common/request/FilterQueryMap.java

@@ -457,4 +457,3 @@ private static <S extends org.apache.thrift.scheme.IScheme> S scheme(org.apache.
     return (org.apache.thrift.scheme.StandardScheme.class.equals(proto.getScheme()) ? STANDARD_SCHEME_FACTORY : TUPLE_SCHEME_FACTORY).getScheme();
   }
 }
-