fe/src/main/java/org/apache/impala/catalog/HiveStorageDescriptorFactory.java

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// to you under the Apache License, Version 2.0 (the
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//   http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.impala.catalog;

import java.util.HashMap;

import org.apache.hadoop.hive.metastore.api.SerDeInfo;
import org.apache.hadoop.hive.metastore.api.StorageDescriptor;
import org.apache.impala.thrift.THdfsFileFormat;

import com.google.common.base.Preconditions;

public class HiveStorageDescriptorFactory {
  /**
   * Creates and returns a Hive StoreDescriptor for the given FileFormat and RowFormat.
   * Currently supports creating StorageDescriptors for Parquet, Text, Sequence, Avro and
   * RC file.
   * TODO: Add support for HBase
   */
  public static StorageDescriptor createSd(THdfsFileFormat fileFormat,
      RowFormat rowFormat) {
    Preconditions.checkNotNull(fileFormat);
    Preconditions.checkNotNull(rowFormat);

    StorageDescriptor sd = new StorageDescriptor();
    sd.setSerdeInfo(new org.apache.hadoop.hive.metastore.api.SerDeInfo());
    sd.getSerdeInfo().setParameters(new HashMap<>());
    // The compressed flag is not used to determine whether the table is compressed or
    // not. Instead, we use the input format or the filename.
    sd.setCompressed(false);
    HdfsFileFormat hdfsFileFormat = HdfsFileFormat.fromThrift(fileFormat);
    sd.setInputFormat(hdfsFileFormat.inputFormat());
    sd.setOutputFormat(hdfsFileFormat.outputFormat());
    sd.getSerdeInfo().setSerializationLib(hdfsFileFormat.serializationLib());
    setSerdeInfo(rowFormat, sd.getSerdeInfo());
    return sd;
  }

  /**
   * Updates the serde info with the specified RowFormat. This method is used when
   * just updating the row format and not the entire storage descriptor.
   */
  public static void setSerdeInfo(RowFormat rowFormat, SerDeInfo serdeInfo) {
    if (rowFormat.getFieldDelimiter() != null) {
      serdeInfo.putToParameters(
          "serialization.format", rowFormat.getFieldDelimiter());
      serdeInfo.putToParameters("field.delim", rowFormat.getFieldDelimiter());
    }
    if (rowFormat.getEscapeChar() != null) {
      serdeInfo.putToParameters("escape.delim", rowFormat.getEscapeChar());
    }
    if (rowFormat.getLineDelimiter() != null) {
      serdeInfo.putToParameters("line.delim", rowFormat.getLineDelimiter());
    }

  }
}