RoaringDocIdSet

java.lang.Object
- org.apache.lucene.search.DocIdSet
- - org.apache.lucene.util.RoaringDocIdSet

All Implemented Interfaces:

Accountable
```
public class RoaringDocIdSet
extends DocIdSet
```
DocIdSet implementation inspired from http://roaringbitmap.org/ The space is divided into blocks of 2^16 bits and each block is encoded independently. In each block, if less than 2^12 bits are set, then documents are simply stored in a short[]. If more than 2^16-2^12 bits are set, then the inverse of the set is encoded in a simple short[]. Otherwise a FixedBitSet is used.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`RoaringDocIdSet.Builder`	A builder of `RoaringDocIdSet`s.
`private class`	`RoaringDocIdSet.Iterator`
`private static class`	`RoaringDocIdSet.ShortArrayDocIdSet`	`DocIdSet` implementation that can store documents up to 2^16-1 in a short[].

Field Summary

Fields
Modifier and Type	Field	Description
`private static long`	`BASE_RAM_BYTES_USED`
`private static int`	`BLOCK_SIZE`
`private int`	`cardinality`
`private DocIdSet[]`	`docIdSets`
`private static int`	`MAX_ARRAY_LENGTH`
`private long`	`ramBytesUsed`

Fields inherited from class org.apache.lucene.search.DocIdSet
EMPTY

Fields inherited from interface org.apache.lucene.util.Accountable
NULL_ACCOUNTABLE

Constructor Summary

Constructors
Modifier Constructor Description

private RoaringDocIdSet(DocIdSet[] docIdSets, int cardinality)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`cardinality()`	Return the exact number of documents that are contained in this set.
`DocIdSetIterator`	`iterator()`	Provides a `DocIdSetIterator` to access the set.
`long`	`ramBytesUsed()`	Return the memory usage of this object in bytes.
`java.lang.String`	`toString()`

Methods inherited from class org.apache.lucene.search.DocIdSet
bits

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.lucene.util.Accountable
getChildResources

- Field Detail
  - BLOCK_SIZE
```
private static final int BLOCK_SIZE
```
    See Also:
    
    Constant Field Values
  - MAX_ARRAY_LENGTH
```
private static final int MAX_ARRAY_LENGTH
```
    See Also:
    
    Constant Field Values
  - BASE_RAM_BYTES_USED
```
private static final long BASE_RAM_BYTES_USED
```
  - docIdSets
```
private final DocIdSet[] docIdSets
```
  - cardinality
```
private final int cardinality
```
  - ramBytesUsed
```
private final long ramBytesUsed
```
- Constructor Detail
  - RoaringDocIdSet
```
private RoaringDocIdSet(DocIdSet[] docIdSets,
                        int cardinality)
```
- Method Detail
  - ramBytesUsed
```
public long ramBytesUsed()
```
    Description copied from interface: Accountable
    
    Return the memory usage of this object in bytes. Negative values are illegal.
  - iterator
```
public DocIdSetIterator iterator()
                          throws java.io.IOException
```
    Description copied from class: DocIdSet
    
    Provides a DocIdSetIterator to access the set. This implementation can return null if there are no docs that match.
    
    Specified by:
    
    iterator in class DocIdSet
    
    Throws:
    
    java.io.IOException
  - cardinality
```
public int cardinality()
```
    Return the exact number of documents that are contained in this set.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object