MetadataCollector (apache-cassandra API)
Date: 2014-10-21

org.apache.cassandra.io.sstable.metadata

## Class MetadataCollector

- java.lang.Object
- - org.apache.cassandra.io.sstable.metadata.MetadataCollector

-     public class MetadataCollector
      extends java.lang.Object

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected java.util.Set<java.lang.Integer>` | `ancestors`
    `protected com.clearspring.analytics.stream.cardinality.ICardinality` | `cardinality` Default cardinality estimation method is to use HyperLogLog++.
    `protected double` | `compressionRatio`
    `protected EstimatedHistogram` | `estimatedColumnCount`
    `protected EstimatedHistogram` | `estimatedRowSize`
    `protected StreamingHistogram` | `estimatedTombstoneDropTime`
    `protected boolean` | `hasLegacyCounterShards`
    `protected java.util.List<java.nio.ByteBuffer>` | `maxColumnNames`
    `protected int` | `maxLocalDeletionTime`
    `protected long` | `maxTimestamp`
    `protected java.util.List<java.nio.ByteBuffer>` | `minColumnNames`
    `protected long` | `minTimestamp`
    `static double` | `NO_COMPRESSION_RATIO`
    `protected ReplayPosition` | `replayPosition`
    `protected int` | `sstableLevel`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `MetadataCollector(CellNameType columnNameComparator)`
    `MetadataCollector(java.util.Collection<SSTableReader> sstables, CellNameType columnNameComparator, int level)`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `MetadataCollector` | `addAncestor(int generation)`
    `MetadataCollector` | `addColumnCount(long columnCount)`
    `MetadataCollector` | `addCompressionRatio(long compressed, long uncompressed)` Ratio is compressed/uncompressed and it is if you have 1.x then compression isn't helping
    `MetadataCollector` | `addKey(java.nio.ByteBuffer key)`
    `MetadataCollector` | `addRowSize(long rowSize)`
    `static StatsMetadata` | `defaultStatsMetadata()`
    `MetadataCollector` | `estimatedColumnCount(EstimatedHistogram estimatedColumnCount)`
    `MetadataCollector` | `estimatedRowSize(EstimatedHistogram estimatedRowSize)`
    `java.util.Map<MetadataType,MetadataComponent>` | `finalizeMetadata(java.lang.String partitioner, double bloomFilterFPChance, long repairedAt)`
    `MetadataCollector` | `mergeTombstoneHistogram(StreamingHistogram histogram)`
    `MetadataCollector` | `replayPosition(ReplayPosition replayPosition)`
    `MetadataCollector` | `sstableLevel(int sstableLevel)`
    `MetadataCollector` | `update(long rowSize, ColumnStats stats)`
    `MetadataCollector` | `updateHasLegacyCounterShards(boolean hasLegacyCounterShards)`
    `MetadataCollector` | `updateMaxColumnNames(java.util.List<java.nio.ByteBuffer> maxColumnNames)`
    `MetadataCollector` | `updateMaxLocalDeletionTime(int maxLocalDeletionTime)`
    `MetadataCollector` | `updateMaxTimestamp(long potentialMax)`
    `MetadataCollector` | `updateMinColumnNames(java.util.List<java.nio.ByteBuffer> minColumnNames)`
    `MetadataCollector` | `updateMinTimestamp(long potentialMin)`

    - ### Methods inherited from class java.lang.Object

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

- - ### Field Detail

    - #### NO_COMPRESSION_RATIO

          public static final double NO_COMPRESSION_RATIO

      See Also:
        Constant Field Values

    - #### estimatedRowSize

          protected EstimatedHistogram estimatedRowSize

    - #### estimatedColumnCount

          protected EstimatedHistogram estimatedColumnCount

    - #### replayPosition

          protected ReplayPosition replayPosition

    - #### minTimestamp

          protected long minTimestamp

    - #### maxTimestamp

          protected long maxTimestamp

    - #### maxLocalDeletionTime

          protected int maxLocalDeletionTime

    - #### compressionRatio

          protected double compressionRatio

    - #### ancestors

          protected java.util.Set<java.lang.Integer> ancestors

    - #### estimatedTombstoneDropTime

          protected StreamingHistogram estimatedTombstoneDropTime

    - #### sstableLevel

          protected int sstableLevel

    - #### minColumnNames

          protected java.util.List<java.nio.ByteBuffer> minColumnNames

    - #### maxColumnNames

          protected java.util.List<java.nio.ByteBuffer> maxColumnNames

    - #### hasLegacyCounterShards

          protected boolean hasLegacyCounterShards

    - #### cardinality

          protected com.clearspring.analytics.stream.cardinality.ICardinality cardinality

      Default cardinality estimation method is to use HyperLogLog++. Parameter here(p=13, sp=25) should give reasonable estimation while lowering bytes required to hold information. See CASSANDRA-5906 for detail.

  - ### Constructor Detail

    - #### MetadataCollector

          public MetadataCollector(CellNameType columnNameComparator)

    - #### MetadataCollector

          public MetadataCollector(java.util.Collection<SSTableReader> sstables,
                           CellNameType columnNameComparator,
                           int level)

  - ### Method Detail

    - #### defaultStatsMetadata

          public static StatsMetadata defaultStatsMetadata()

    - #### addKey

          public MetadataCollector addKey(java.nio.ByteBuffer key)

    - #### addRowSize

          public MetadataCollector addRowSize(long rowSize)

    - #### addColumnCount

          public MetadataCollector addColumnCount(long columnCount)

    - #### mergeTombstoneHistogram

          public MetadataCollector mergeTombstoneHistogram(StreamingHistogram histogram)

    - #### addCompressionRatio

          public MetadataCollector addCompressionRatio(long compressed,
                                              long uncompressed)

      Ratio is compressed/uncompressed and it is if you have 1.x then compression isn't helping

    - #### updateMinTimestamp

          public MetadataCollector updateMinTimestamp(long potentialMin)

    - #### updateMaxTimestamp

          public MetadataCollector updateMaxTimestamp(long potentialMax)

    - #### updateMaxLocalDeletionTime

          public MetadataCollector updateMaxLocalDeletionTime(int maxLocalDeletionTime)

    - #### estimatedRowSize

          public MetadataCollector estimatedRowSize(EstimatedHistogram estimatedRowSize)

    - #### estimatedColumnCount

          public MetadataCollector estimatedColumnCount(EstimatedHistogram estimatedColumnCount)

    - #### replayPosition

          public MetadataCollector replayPosition(ReplayPosition replayPosition)

    - #### addAncestor

          public MetadataCollector addAncestor(int generation)

    - #### sstableLevel

          public MetadataCollector sstableLevel(int sstableLevel)

    - #### updateMinColumnNames

          public MetadataCollector updateMinColumnNames(java.util.List<java.nio.ByteBuffer> minColumnNames)

    - #### updateMaxColumnNames

          public MetadataCollector updateMaxColumnNames(java.util.List<java.nio.ByteBuffer> maxColumnNames)

    - #### updateHasLegacyCounterShards

          public MetadataCollector updateHasLegacyCounterShards(boolean hasLegacyCounterShards)

    - #### update

          public MetadataCollector update(long rowSize,
                                 ColumnStats stats)

    - #### finalizeMetadata

          public java.util.Map<MetadataType,MetadataComponent> finalizeMetadata(java.lang.String partitioner,
                                                                       double bloomFilterFPChance,
                                                                       long repairedAt)

Copyright © 2014 The Apache Software Foundation