Module roaringbitmap
Package org.roaringbitmap

Class RoaringBitmapWriter.Wizard<C extends WordStorage<C>,​T extends BitmapDataProvider & AppendableStorage<C>>

java.lang.Object
org.roaringbitmap.RoaringBitmapWriter.Wizard<C,​T>
All Implemented Interfaces:
Supplier<RoaringBitmapWriter<T>>
Direct Known Subclasses:
RoaringBitmapWriter.BufferWizard, RoaringBitmapWriter.RoaringWizard
Enclosing interface:
RoaringBitmapWriter<T extends BitmapDataProvider>
public abstract static class RoaringBitmapWriter.Wizard<C extends WordStorage<C>,​T extends BitmapDataProvider & AppendableStorage<C>> extends Object implements Supplier<RoaringBitmapWriter<T>>

  • Field Details

    • initialCapacity

      protected int initialCapacity

    • constantMemory

      protected boolean constantMemory

    • partiallySortValues

      protected boolean partiallySortValues

    • runCompress

      protected boolean runCompress

    • containerSupplier

      protected Supplier<C extends WordStorage<C>> containerSupplier

    • expectedContainerSize

      protected int expectedContainerSize

  • Method Details

    • optimiseForArrays

      public RoaringBitmapWriter.Wizard<C,​T> optimiseForArrays()
      Choose this option if it is known that most containers will be sparse.
      Returns:
      this

    • optimiseForRuns

      public RoaringBitmapWriter.Wizard<C,​T> optimiseForRuns()
      Choose this option if the bitmap is expected to be RLE compressible. Will buffer additions into a RunContainer.
      Returns:
      this

    • runCompress

      public RoaringBitmapWriter.Wizard<C,​T> runCompress​(boolean runCompress)
      By default the bitmap will be run-compressed on the fly, but it can be disabled (and run compressed at the end).
      Parameters:
      runCompress - whether to apply run compression on the fly.
      Returns:
      this

    • expectedValuesPerContainer

      public RoaringBitmapWriter.Wizard<C,​T> expectedValuesPerContainer​(int count)
      Parameters:
      count - how many values are expected to fall within any 65536 bit range.
      Returns:
      this

    • fastRank

      public RoaringBitmapWriter.Wizard<Container,​FastRankRoaringBitmap> fastRank()

    • constantMemory

      public RoaringBitmapWriter.Wizard<C,​T> constantMemory()
      All writes are buffered into the same buffer of 8kB, before converting to the best container representation and appending to the bitmap. This option overrides any optimiseForArrays, optimiseForRuns and optimiseForBitmaps settings.
      Returns:
      this

    • expectedDensity

      public RoaringBitmapWriter.Wizard<C,​T> expectedDensity​(double density)
      Influence default container choice by how dense the bitmap is expected to be.
      Parameters:
      density - value in [0.0, 1.0], density of the bitmap
      Returns:
      this

    • expectedRange

      public RoaringBitmapWriter.Wizard<C,​T> expectedRange​(long min, long max)
      Guesses the number of prefices required based on an estimate of the range the bitmap will contain, assumes that all prefices in the range will be required. This is a good heuristic for a contiguous bitmap, and, for instance, a very bad heuristic for a bitmap with just two values far apart.
      Parameters:
      min - the inclusive min value
      max - the exclusive max value
      Returns:
      this

    • initialCapacity

      public RoaringBitmapWriter.Wizard<C,​T> initialCapacity​(int count)
      Takes control of the size of the prefix array, in case it can be precalculated or estimated. This can potentially save many array allocations during building the bitmap.
      Parameters:
      count - an estimate of the number of prefix keys required.
      Returns:
      this

    • doPartialRadixSort

      public RoaringBitmapWriter.Wizard<C,​T> doPartialRadixSort()
      Will partially sort values, which can allocate O(n) temporary memory but can significantly speed up adding unsorted values to a bitmap.
      Returns:
      this

    • arraySupplier

      protected abstract Supplier<C> arraySupplier()

    • runSupplier

      protected abstract Supplier<C> runSupplier()

    • createUnderlying

      protected abstract T createUnderlying​(int initialCapacity)

    • get

      public RoaringBitmapWriter<T> get()
      Builds a bitmap writer based on the supplied options. A call to this method is repeatable, and will not fail because the wizard should already be in a valid state.
      Specified by:
      get in interface Supplier<C extends WordStorage<C>>
      Returns:
      a new RoaringBitmapWriter