Github user ravipesala commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/2374#discussion_r197016418
--- Diff: hadoop/src/main/java/org/apache/carbondata/hadoop/CsvRecordReader.java ---
@@ -0,0 +1,506 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *
http://www.apache.org/licenses/LICENSE-2.0 + *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.carbondata.hadoop;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.Reader;
+import java.io.UnsupportedEncodingException;
+import java.math.BigDecimal;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.carbondata.common.annotations.InterfaceAudience;
+import org.apache.carbondata.common.annotations.InterfaceStability;
+import org.apache.carbondata.common.logging.LogService;
+import org.apache.carbondata.common.logging.LogServiceFactory;
+import org.apache.carbondata.core.constants.CarbonCommonConstants;
+import org.apache.carbondata.core.constants.CarbonV3DataFormatConstants;
+import org.apache.carbondata.core.datastore.block.SegmentProperties;
+import org.apache.carbondata.core.metadata.schema.table.CarbonTable;
+import org.apache.carbondata.core.metadata.schema.table.column.CarbonColumn;
+import org.apache.carbondata.core.metadata.schema.table.column.CarbonDimension;
+import org.apache.carbondata.core.metadata.schema.table.column.CarbonMeasure;
+import org.apache.carbondata.core.metadata.schema.table.column.ColumnSchema;
+import org.apache.carbondata.core.scan.expression.exception.FilterUnsupportedException;
+import org.apache.carbondata.core.scan.filter.FilterUtil;
+import org.apache.carbondata.core.scan.filter.GenericQueryType;
+import org.apache.carbondata.core.scan.filter.executer.FilterExecuter;
+import org.apache.carbondata.core.scan.filter.intf.RowImpl;
+import org.apache.carbondata.core.scan.filter.intf.RowIntf;
+import org.apache.carbondata.core.scan.filter.resolver.FilterResolverIntf;
+import org.apache.carbondata.core.scan.model.QueryModel;
+import org.apache.carbondata.core.statusmanager.FileFormatProperties;
+import org.apache.carbondata.core.util.CarbonUtil;
+import org.apache.carbondata.core.util.DataTypeUtil;
+import org.apache.carbondata.hadoop.api.CarbonTableInputFormat;
+import org.apache.carbondata.hadoop.readsupport.CarbonReadSupport;
+import org.apache.carbondata.processing.loading.csvinput.CSVInputFormat;
+
+import com.univocity.parsers.csv.CsvParser;
+import com.univocity.parsers.csv.CsvParserSettings;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FSDataInputStream;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.mapreduce.InputSplit;
+import org.apache.hadoop.mapreduce.TaskAttemptContext;
+import org.apache.hadoop.mapreduce.lib.input.FileSplit;
+
+/**
+ * scan csv file and filter on it
+ */
+@InterfaceStability.Evolving
+@InterfaceAudience.Internal
+public class CsvRecordReader<T> extends AbstractRecordReader<T> {
+ private static final LogService LOGGER = LogServiceFactory.getLogService(
+ CsvRecordReader.class.getName());
+ private static final int MAX_BATCH_SIZE =
+ CarbonV3DataFormatConstants.NUMBER_OF_ROWS_PER_BLOCKLET_COLUMN_PAGE_DEFAULT;
+ // vector reader
+ private boolean isVectorReader;
+ private T columnarBatch;
+
+ // metadata
+ private CarbonTable carbonTable;
+ private CarbonColumn[] carbonColumns;
+ // input
+ private QueryModel queryModel;
+ private CarbonReadSupport<T> readSupport;
+ private FileSplit fileSplit;
+ private Configuration hadoopConf;
+ // the index is schema ordinal, the value is the csv ordinal
+ private int[] schema2csvIdx;
+
+ // filter
+ private FilterExecuter filter;
--- End diff --
FIltering logic should be out of readers. Because in future if we add more readers, not every reader should handle it.
So the design should be like on top of reader we should have a filter class.
---
Locked
