Class IteratorAggregation

java.lang.Object
com.googlecode.javaewah.IteratorAggregation
public final class IteratorAggregation extends Object
Set of helper functions to aggregate bitmaps.

  • Field Details

    • DEFAULT_MAX_BUF_SIZE

      public static final int DEFAULT_MAX_BUF_SIZE
      An optimization option. Larger values may improve speed, but at the expense of memory.
      See Also:

  • Constructor Details

    • IteratorAggregation

      private IteratorAggregation()
      Private constructor to prevent instantiation

  • Method Details

    • not

      public static IteratingRLW not(IteratingRLW x)
      Parameters:
      x - iterator to negate
      Returns:
      negated version of the iterator

    • bufferedand

      public static IteratingRLW bufferedand(IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      al - set of iterators to aggregate
      Returns:
      and aggregate

    • bufferedand

      public static IteratingRLW bufferedand(int bufSize, IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      bufSize - size of the internal buffer used by the iterator in 64-bit words (per input iterator)
      al - set of iterators to aggregate
      Returns:
      and aggregate

    • bufferedor

      public static IteratingRLW bufferedor(IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      al - set of iterators to aggregate
      Returns:
      or aggregate

    • bufferedor

      public static IteratingRLW bufferedor(int bufSize, IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      bufSize - size of the internal buffer used by the iterator in 64-bit words
      al - iterators to aggregate
      Returns:
      or aggregate

    • bufferedxor

      public static IteratingRLW bufferedxor(IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      al - set of iterators to aggregate
      Returns:
      xor aggregate

    • bufferedxor

      public static IteratingRLW bufferedxor(int bufSize, IteratingRLW... al)
      Aggregate the iterators using a bitmap buffer.
      Parameters:
      bufSize - size of the internal buffer used by the iterator in 64-bit words
      al - iterators to aggregate
      Returns:
      xor aggregate

    • dischargeAsEmpty

      protected static void dischargeAsEmpty(BitmapStorage container, IteratingRLW i)
      Write out the content of the iterator, but as if it were all zeros.
      Parameters:
      container - where we write
      i - the iterator

    • discharge

      protected static long discharge(BitmapStorage container, IteratingRLW i, long max)
      Write out up to max words, returns how many were written
      Parameters:
      container - target for writes
      i - source of data
      max - maximal number of writes
      Returns:
      how many written

    • dischargeNegated

      protected static long dischargeNegated(BitmapStorage container, IteratingRLW i, long max)
      Write out up to max negated words, returns how many were written
      Parameters:
      container - target for writes
      i - source of data
      max - maximal number of writes
      Returns:
      how many written

    • andToContainer

      static void andToContainer(BitmapStorage container, int desiredrlwcount, IteratingRLW rlwi, IteratingRLW rlwj)

    • andToContainer

      static void andToContainer(BitmapStorage container, IteratingRLW rlwi, IteratingRLW rlwj)

    • xorToContainer

      public static void xorToContainer(BitmapStorage container, int desiredrlwcount, IteratingRLW rlwi, IteratingRLW rlwj)
      Compute the first few words of the XOR aggregate between two iterators.
      Parameters:
      container - where to write
      desiredrlwcount - number of words to be written (max)
      rlwi - first iterator to aggregate
      rlwj - second iterator to aggregate

    • inplaceor

      protected static int inplaceor(long[] bitmap, IteratingRLW i)

    • inplacexor

      protected static int inplacexor(long[] bitmap, IteratingRLW i)

    • inplaceand

      protected static int inplaceand(long[] bitmap, IteratingRLW i)