[MINOR] Remove unused imports and some other checkstyle issues (#2800)

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/converter/DeleteConverter.java

@@ -24,8 +24,6 @@ import org.apache.hudi.integ.testsuite.generator.LazyRecordGeneratorIterator;
 import org.apache.avro.generic.GenericRecord;
 import org.apache.spark.api.java.JavaRDD;
 
-import java.util.List;
-
 public class DeleteConverter implements Converter<GenericRecord, GenericRecord> {
 
   private final String schemaStr;

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/dag/DagUtils.java

@@ -50,11 +50,6 @@ import java.util.Map.Entry;
 import java.util.stream.Collectors;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hudi.common.util.ReflectionUtils;
-import org.apache.hudi.common.util.StringUtils;
-import org.apache.hudi.common.util.collection.Pair;
-import org.apache.hudi.integ.testsuite.configuration.DeltaConfig;
-import org.apache.hudi.integ.testsuite.dag.nodes.DagNode;
 
 /**
  * Utility class to SerDe workflow dag.

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/dag/scheduler/DagScheduler.java

@@ -27,7 +27,6 @@ import org.apache.hudi.integ.testsuite.dag.nodes.DelayNode;
 import org.apache.hudi.metrics.Metrics;
 
 import org.apache.spark.api.java.JavaSparkContext;
-import org.junit.runners.Suite;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/dag/scheduler/SaferSchemaDagScheduler.java

@@ -19,7 +19,6 @@
 package org.apache.hudi.integ.testsuite.dag.scheduler;
 
 import org.apache.hudi.exception.HoodieException;
-import org.apache.hudi.integ.testsuite.dag.scheduler.DagScheduler;
 import org.apache.hudi.integ.testsuite.dag.WorkflowDag;
 import org.apache.hudi.integ.testsuite.dag.WriterContext;
 import org.apache.hudi.integ.testsuite.dag.nodes.DagNode;

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/generator/DeleteGeneratorIterator.java

@@ -21,9 +21,7 @@ package org.apache.hudi.integ.testsuite.generator;
 import org.apache.avro.Schema;
 import org.apache.avro.generic.GenericRecord;
 
-import java.util.ArrayList;
 import java.util.Iterator;
-import java.util.List;
 
 /**
  * Lazy delete record generator.

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/generator/DeltaGenerator.java

@@ -28,7 +28,6 @@ import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
-import java.util.UUID;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 import java.util.stream.StreamSupport;
@@ -41,10 +40,6 @@ import org.apache.hudi.integ.testsuite.configuration.DFSDeltaConfig;
 import org.apache.hudi.integ.testsuite.configuration.DeltaConfig.Config;
 import org.apache.hudi.integ.testsuite.converter.Converter;
 import org.apache.hudi.integ.testsuite.converter.DeleteConverter;
-import org.apache.hudi.common.util.Option;
-import org.apache.hudi.integ.testsuite.configuration.DFSDeltaConfig;
-import org.apache.hudi.integ.testsuite.configuration.DeltaConfig;
-import org.apache.hudi.integ.testsuite.configuration.DeltaConfig.Config;
 import org.apache.hudi.integ.testsuite.converter.UpdateConverter;
 import org.apache.hudi.integ.testsuite.reader.DFSAvroDeltaInputReader;
 import org.apache.hudi.integ.testsuite.reader.DFSHoodieDatasetInputReader;
@@ -55,7 +50,6 @@ import org.apache.hudi.integ.testsuite.writer.DeltaWriterAdapter;
 import org.apache.hudi.integ.testsuite.writer.DeltaWriterFactory;
 import org.apache.hudi.keygen.BuiltinKeyGenerator;
 
-import org.apache.avro.generic.GenericRecord;
 import org.apache.spark.api.java.JavaRDD;
 import org.apache.spark.api.java.JavaSparkContext;
 import org.apache.spark.sql.SparkSession;
@@ -63,18 +57,6 @@ import org.apache.spark.storage.StorageLevel;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.IOException;
-import java.io.Serializable;
-import java.io.UncheckedIOException;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.StreamSupport;
-
 import scala.Tuple2;
 
 /**
@@ -235,7 +217,6 @@ public class DeltaGenerator implements Serializable {
     }
   }
 
-
   public Map<Integer, Long> getPartitionToCountMap(JavaRDD<GenericRecord> records) {
     // Requires us to keep the partitioner the same
     return records.mapPartitionsWithIndex((index, itr) -> {

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/generator/GenericRecordFullPayloadGenerator.java

@@ -27,7 +27,6 @@ import org.apache.avro.generic.GenericData;
 import org.apache.avro.generic.GenericData.Fixed;
 import org.apache.avro.generic.GenericFixed;
 import org.apache.avro.generic.GenericRecord;
-import org.junit.runners.Suite;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hudi-integ-test/src/main/java/org/apache/hudi/integ/testsuite/writer/DFSDeltaWriterAdapter.java

@@ -18,8 +18,6 @@
 
 package org.apache.hudi.integ.testsuite.writer;
 
-import org.apache.hudi.integ.testsuite.schema.SchemaUtils;
-
 import org.apache.avro.generic.GenericRecord;
 
 import java.io.IOException;

hudi-integ-test/src/test/java/org/apache/hudi/integ/testsuite/converter/TestDeleteConverter.java

@@ -28,7 +28,6 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 

hudi-integ-test/src/test/java/org/apache/hudi/integ/testsuite/converter/TestUpdateConverter.java

@@ -20,7 +20,6 @@ package org.apache.hudi.integ.testsuite.converter;
 
 import static junit.framework.TestCase.assertTrue;
 
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;

hudi-spark-datasource/hudi-spark3/src/main/java/org/apache/hudi/spark3/internal/HoodieDataSourceInternalTable.java

@@ -66,7 +66,8 @@ class HoodieDataSourceInternalTable implements SupportsWrite {
     return new HashSet<TableCapability>() {{
         add(TableCapability.BATCH_WRITE);
         add(TableCapability.TRUNCATE);
-      }};
+      }
+    };
   }
 
   @Override