org.apache.druid.segment.nested

Class NestedDataColumnSerializer

java.lang.Object

org.apache.druid.segment.nested.NestedCommonFormatColumnSerializer

org.apache.druid.segment.nested.NestedDataColumnSerializer

All Implemented Interfaces:

GenericColumnSerializer<StructuredData>, Serializer

public class NestedDataColumnSerializer
extends NestedCommonFormatColumnSerializer

Serializer for NestedCommonFormatColumn which can store nested data. The serializer stores several components including: - a field list and associated type info - value dictionaries for string, long, double, and array values (where the arrays are stored as int[] that point to the string, long, and double values) - raw data is stored with a CompressedVariableSizedBlobColumnSerializer as blobs of SMILE encoded data - a null value bitmap to track which 'raw' rows are null For each nested field, a GlobalDictionaryEncodedFieldColumnWriter will write a sub-column to specialize fast reading and filtering of that path.

See Also:

- single type double field, - single type long field, - single type string field, - single type array of string, long, and double field, - mixed type field

Field Summary

Fields inherited from class org.apache.druid.segment.nested.NestedCommonFormatColumnSerializer

ARRAY_DICTIONARY_FILE_NAME, ARRAY_ELEMENT_BITMAP_INDEX_FILE_NAME, ARRAY_ELEMENT_DICTIONARY_FILE_NAME, BITMAP_INDEX_FILE_NAME, DOUBLE_DICTIONARY_FILE_NAME, DOUBLE_VALUE_COLUMN_FILE_NAME, ENCODED_VALUE_COLUMN_FILE_NAME, LONG_DICTIONARY_FILE_NAME, LONG_VALUE_COLUMN_FILE_NAME, NESTED_FIELD_PREFIX, NULL_BITMAP_FILE_NAME, RAW_FILE_NAME, STRING_DICTIONARY_FILE_NAME, V0

Constructor Summary

Constructors

Constructor and Description
NestedDataColumnSerializer(String name, IndexSpec indexSpec, SegmentWriteOutMedium segmentWriteOutMedium, Closer closer)

Method Summary

Modifier and Type	Method and Description
String	getColumnName()
DictionaryIdLookup	getGlobalLookup()
long	getSerializedSize() Returns the number of bytes, that this Serializer will write to the output _channel_ (not smoosher) on a Serializer.writeTo(java.nio.channels.WritableByteChannel, org.apache.druid.java.util.common.io.smoosh.FileSmoosher) call.
boolean	hasNulls()
void	open()
void	openDictionaryWriter()
void	serialize(ColumnValueSelector<? extends StructuredData> selector)
void	serializeDictionaries(Iterable<String> strings, Iterable<Long> longs, Iterable<Double> doubles, Iterable<int[]> arrays)
void	serializeFields(SortedMap<String,FieldTypeInfo.MutableTypeSet> fields)
void	writeTo(WritableByteChannel channel, FileSmoosher smoosher) Writes serialized form of this object to the given channel.

Methods inherited from class org.apache.druid.segment.nested.NestedCommonFormatColumnSerializer

computeFilenameBytes, getInternalFileName, writeInternal, writeV0Header

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NestedDataColumnSerializer

public NestedDataColumnSerializer(String name,
                                  IndexSpec indexSpec,
                                  SegmentWriteOutMedium segmentWriteOutMedium,
                                  Closer closer)

Method Detail

getColumnName

public String getColumnName()

Specified by:

getColumnName in class NestedCommonFormatColumnSerializer

getGlobalLookup

public DictionaryIdLookup getGlobalLookup()

Specified by:

getGlobalLookup in class NestedCommonFormatColumnSerializer

hasNulls

public boolean hasNulls()

Specified by:

hasNulls in class NestedCommonFormatColumnSerializer

openDictionaryWriter

public void openDictionaryWriter()
                          throws IOException

Specified by:

openDictionaryWriter in class NestedCommonFormatColumnSerializer

Throws:

IOException

open

public void open()
          throws IOException

Throws:

IOException

serializeFields

public void serializeFields(SortedMap<String,FieldTypeInfo.MutableTypeSet> fields)
                     throws IOException

Overrides:

serializeFields in class NestedCommonFormatColumnSerializer

Throws:

IOException

serializeDictionaries

public void serializeDictionaries(Iterable<String> strings,
                                  Iterable<Long> longs,
                                  Iterable<Double> doubles,
                                  Iterable<int[]> arrays)
                           throws IOException

Specified by:

serializeDictionaries in class NestedCommonFormatColumnSerializer

Throws:

IOException

serialize

public void serialize(ColumnValueSelector<? extends StructuredData> selector)
               throws IOException

Throws:

IOException

getSerializedSize

public long getSerializedSize()
                       throws IOException

Description copied from interface: Serializer

Returns the number of bytes, that this Serializer will write to the output _channel_ (not smoosher) on a Serializer.writeTo(java.nio.channels.WritableByteChannel, org.apache.druid.java.util.common.io.smoosh.FileSmoosher) call.

Throws:

IOException

writeTo

public void writeTo(WritableByteChannel channel,
                    FileSmoosher smoosher)
             throws IOException

Description copied from interface: Serializer

Writes serialized form of this object to the given channel. If parallel data streams are needed, they could be created with the provided smoosher.

Throws:

IOException