Package io.trino.plugin.accumulo.serializers

Interface AccumuloRowSerializer

All Known Implementing Classes:
LexicoderRowSerializer, StringRowSerializer
public interface AccumuloRowSerializer
Interface for deserializing the data in Accumulo into a Trino row.

Provides a means for end-users of the connector to customize how the data in an Accumulo row gets serialized and deserialized from/to a Trino row.

The workflow of how this class is called by the Accumulo connector for reading data is as follows:

  1. setRowIdName - Sets the Trino name which is the Accumulo row ID
  2. setRowOnly - True if only the row ID is going to be retrieved, false if more data is necessary.
  3. setMapping - Multiple calls for each Trino column, setting the mapping of Trino column name to Accumulo column family and qualifier
  4. deserialize - Called for each Accumulo entry in the same row. Implements should retrieve the Trino column value from the given key/value pair
  5. get* - Called to retrieve the data type for the given Trino column name
  6. reset - Begins a new Row, serializer is expected to clear any state
  7. If there are more entries left, go back to deserialize, else end!
See Also:

  • Method Details

    • getDefault

      static AccumuloRowSerializer getDefault()
      Gets the default AccumuloRowSerializer, LexicoderRowSerializer.
      Returns:
      Default serializer

    • setRowIdName

      void setRowIdName(String name)
      Sets the Trino name which maps to the Accumulo row ID.
      Parameters:
      name - Trino column name

    • setMapping

      void setMapping(String name, String family, String qualifier)
      Sets the mapping for the Trino column name to Accumulo family and qualifier.
      Parameters:
      name - Trino name
      family - Accumulo family
      qualifier - Accumulo qualifier

    • setRowOnly

      void setRowOnly(boolean rowOnly)
      Sets a Boolean value indicating whether or not only the row ID is going to be retrieved from the serializer.
      Parameters:
      rowOnly - True if only the row ID is set, false otherwise

    • reset

      void reset()
      Reset the state of the serializer to prepare for a new set of entries with the same row ID.

    • deserialize

      void deserialize(Map.Entry<org.apache.accumulo.core.data.Key,org.apache.accumulo.core.data.Value> entry)
      Deserialize the given Accumulo entry, retrieving data for the Trino column.
      Parameters:
      entry - Entry to deserialize

    • isNull

      boolean isNull(String name)
      Gets a Boolean value indicating whether or not the Trino column is a null value.
      Parameters:
      name - Column name
      Returns:
      True if null, false otherwise.

    • getArray

      Block getArray(String name, Type type)
      Gets the array Block of the given Trino column.
      Parameters:
      name - Column name
      type - Array type
      Returns:
      True if null, false otherwise.

    • setArray

      void setArray(org.apache.hadoop.io.Text text, Type type, Block block)
      Encode the given array Block into the given Text object.
      Parameters:
      text - Text object to set
      type - Array type
      block - Array block

    • getBoolean

      boolean getBoolean(String name)
      Gets the Boolean value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Boolean value

    • setBoolean

      void setBoolean(org.apache.hadoop.io.Text text, Boolean value)
      Encode the given Boolean value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getByte

      byte getByte(String name)
      Gets the Byte value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Byte value

    • setByte

      void setByte(org.apache.hadoop.io.Text text, Byte value)
      Encode the given Byte value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getDate

      long getDate(String name)
      Gets the Date value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Date value

    • setDate

      void setDate(org.apache.hadoop.io.Text text, long value)
      Encode the given Date value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getDouble

      double getDouble(String name)
      Gets the Double value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Double value

    • setDouble

      void setDouble(org.apache.hadoop.io.Text text, Double value)
      Encode the given Double value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getFloat

      float getFloat(String name)
      Gets the Float value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Float value

    • setFloat

      void setFloat(org.apache.hadoop.io.Text text, Float value)
      Encode the given Float value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getInt

      int getInt(String name)
      Gets the Integer value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Integer value

    • setInt

      void setInt(org.apache.hadoop.io.Text text, Integer value)
      Encode the given Integer value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getLong

      long getLong(String name)
      Gets the Long value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Long value

    • setLong

      void setLong(org.apache.hadoop.io.Text text, Long value)
      Encode the given Long value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getMap

      Block getMap(String name, Type type)
      Gets the Map value of the given Trino column and Map type.
      Parameters:
      name - Column name
      type - Map type
      Returns:
      Map value

    • setMap

      void setMap(org.apache.hadoop.io.Text text, Type type, Block block)
      Encode the given map Block into the given Text object.
      Parameters:
      text - Text object to set
      type - Map type
      block - Map block

    • getShort

      short getShort(String name)
      Gets the Short value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Short value

    • setShort

      void setShort(org.apache.hadoop.io.Text text, Short value)
      Encode the given Short value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getTime

      Time getTime(String name)
      Gets the Time value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Time value

    • setTime

      void setTime(org.apache.hadoop.io.Text text, Time value)
      Encode the given Time value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getTimestamp

      Timestamp getTimestamp(String name)
      Gets the Timestamp value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Timestamp value

    • setTimestamp

      void setTimestamp(org.apache.hadoop.io.Text text, Timestamp value)
      Encode the given Timestamp value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getVarbinary

      byte[] getVarbinary(String name)
      Gets the Varbinary value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      Varbinary value

    • setVarbinary

      void setVarbinary(org.apache.hadoop.io.Text text, byte[] value)
      Encode the given byte[] value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • getVarchar

      String getVarchar(String name)
      Gets the String value of the given Trino column.
      Parameters:
      name - Column name
      Returns:
      String value

    • setVarchar

      void setVarchar(org.apache.hadoop.io.Text text, String value)
      Encode the given String value into the given Text object.
      Parameters:
      text - Text object to set
      value - Value to encode

    • encode

      byte[] encode(Type type, Object value)
      Encodes a Trino Java object to a byte array based on the given type.

      Java Lists and Maps can be converted to Blocks using getBlockFromArray(Type, java.util.List) and getBlockFromMap(Type, Map)

      Type to Encode Expected Java Object
      ARRAY io.trino.spi.block.Block
      BIGINT Integer or Long
      BOOLEAN Boolean
      DATE long
      DOUBLE Double
      INTEGER Integer
      Map io.trino.spi.block.Block
      REAL Float
      SMALLINT Short
      TIME java.sql.Time, Long
      TIMESTAMP java.sql.Timestamp, Long
      TINYINT Byte
      VARBINARY io.airlift.slice.Slice or byte[]
      VARCHAR io.airlift.slice.Slice or String
      Parameters:
      type - The Trino Type
      value - The Java object per the table in the method description
      Returns:
      Encoded bytes

    • decode

      <T> T decode(Type type, byte[] value)
      Generic function to decode the given byte array to a Java object based on the given type.

      Blocks from ARRAY and MAP types can be converted to Java Lists and Maps using getArrayFromBlock(Type, Block) and getMapFromBlock(Type, Block)

      Encoded Type Returned Java Object
      ARRAY List<?>
      BIGINT Long
      BOOLEAN Boolean
      DATE Long
      DOUBLE Double
      Map Map<?,?>
      REAL Double
      SMALLINT Long
      TIME Long
      TIMESTAMP Long
      TINYINT Long
      VARBINARY byte[]
      VARCHAR String
      Type Parameters:
      T - The Java type of the object that has been encoded to the given byte array
      Parameters:
      type - The Trino Type
      value - Encoded bytes to decode
      Returns:
      The Java object per the table in the method description

    • getArrayFromBlock

      static List<Object> getArrayFromBlock(Type elementType, Block block)
      Given the array element type and Trino Block, decodes the Block into a list of values.
      Parameters:
      elementType - Array element type
      block - Array block
      Returns:
      List of values

    • getMapFromBlock

      static Map<Object,Object> getMapFromBlock(Type type, Block block)
      Given the map type and Trino Block, decodes the Block into a map of values.
      Parameters:
      type - Map type
      block - Map block
      Returns:
      List of values

    • getBlockFromArray

      static Block getBlockFromArray(Type elementType, List<?> array)
      Encodes the given list into a Block.
      Parameters:
      elementType - Element type of the array
      array - Array of elements to encode
      Returns:
      Trino Block

    • getBlockFromMap

      static Block getBlockFromMap(Type type, Map<?,?> map)
      Encodes the given map into a Block.
      Parameters:
      type - Trino type of the map
      map - Map of key/value pairs to encode
      Returns:
      Trino Block

    • writeObject

      static void writeObject(BlockBuilder builder, Type type, Object obj)
      Recursive helper function used by getBlockFromArray(io.trino.spi.type.Type, java.util.List<?>) and getBlockFromMap(io.trino.spi.type.Type, java.util.Map<?, ?>) to add the given object to the given block builder. Supports nested complex types!
      Parameters:
      builder - Block builder
      type - Trino type
      obj - Object to write to the block builder

    • readObject

      static Object readObject(Type type, Block block, int position)
      Recursive helper function used by getArrayFromBlock(io.trino.spi.type.Type, io.trino.spi.block.Block) and getMapFromBlock(io.trino.spi.type.Type, io.trino.spi.block.Block) to decode the Block into a Java type.
      Parameters:
      type - Trino type
      block - Block to decode
      position - Position in the block to get
      Returns:
      Java object from the Block