Package com.googlecode.javaewah
Class IteratorUtil
- java.lang.Object
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- com.googlecode.javaewah.IteratorUtil
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public final class IteratorUtil extends Object
Convenience functions for working over iterators
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Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static int
cardinality(IteratingRLW i)
static EWAHCompressedBitmap
materialize(IteratingRLW i)
Turn an iterator into a bitmap.static void
materialize(IteratingRLW i, BitmapStorage c)
Generate a bitmap from an iterator.static long
materialize(IteratingRLW i, BitmapStorage c, long max)
Turn an iterator into a bitmap.static IteratingRLW[]
toIterators(EWAHCompressedBitmap... x)
static IntIterator
toSetBitsIntIterator(IteratingRLW i)
static Iterator<Integer>
toSetBitsIterator(IteratingRLW i)
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Method Detail
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toSetBitsIntIterator
public static IntIterator toSetBitsIntIterator(IteratingRLW i)
- Parameters:
i
- iterator we wish to iterate over- Returns:
- an iterator over the set bits corresponding to the iterator
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toSetBitsIterator
public static Iterator<Integer> toSetBitsIterator(IteratingRLW i)
- Parameters:
i
- iterator we wish to iterate over- Returns:
- an iterator over the set bits corresponding to the iterator
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materialize
public static void materialize(IteratingRLW i, BitmapStorage c)
Generate a bitmap from an iterator.- Parameters:
i
- iterator we wish to materializec
- where we write
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cardinality
public static int cardinality(IteratingRLW i)
- Parameters:
i
- iterator we wish to iterate over- Returns:
- the cardinality (number of set bits) corresponding to the iterator
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toIterators
public static IteratingRLW[] toIterators(EWAHCompressedBitmap... x)
- Parameters:
x
- set of bitmaps- Returns:
- an array of iterators corresponding to the array of bitmaps
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materialize
public static long materialize(IteratingRLW i, BitmapStorage c, long max)
Turn an iterator into a bitmap.- Parameters:
i
- iterator we wish to materializec
- where we writemax
- maximum number of words we wish to materialize- Returns:
- how many words were actually materialized
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materialize
public static EWAHCompressedBitmap materialize(IteratingRLW i)
Turn an iterator into a bitmap. This can be used to effectively clone a bitmap in the following manner:EWAHCompressedBitmap n = IteratorUtil.materialize(bitmap.getIteratingRLW())); n.setSizeInBitsWithinLastWord(bitmap.sizeInBits());
- Parameters:
i
- iterator we wish to materialize- Returns:
- materialized version of the iterator
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