org.apache.solr.search
Class BitDocSet

java.lang.Object
  org.apache.solr.search.BitDocSet

All Implemented Interfaces:

DocSet

public class BitDocSet
extends Object

BitDocSet represents an unordered set of Lucene Document Ids using a BitSet. A set bit represents inclusion in the set for that document.

Since:

solr 0.9

Field Summary

Fields inherited from interface org.apache.solr.search.DocSet

EMPTY

Constructor Summary

BitDocSet()

BitDocSet(FixedBitSet bits)
Construct a BitDocSet.

BitDocSet(FixedBitSet bits, int size)
Construct a BitDocSet, and provides the number of set bits.

Method Summary

void	add(int doc) Adds the specified document if it is not currently in the DocSet (optional operation).
void	addAllTo(DocSet target) Adds all the docs from this set to the target set.
void	addUnique(int doc) Adds a document the caller knows is not currently in the DocSet (optional operation).
DocSet	andNot(DocSet other) Returns the documents in this set that are not in the other set.
int	andNotSize(DocSet other) Returns the number of documents in this set that are not in the other set.
protected BitDocSet	clone()
boolean	equals(Object obj)
boolean	exists(int doc) Returns true of the doc exists in the set.
FixedBitSet	getBits() Return a FixedBitSet with a bit set for every document in this DocSet.
Filter	getTopFilter() Returns a Filter for use in Lucene search methods, assuming this DocSet was generated from the top-level MultiReader that the Lucene search methods will be invoked with.
DocSet	intersection(DocSet other) Returns the intersection of this set with another set.
int	intersectionSize(DocSet other) Returns the number of documents of the intersection of this set with another set.
boolean	intersects(DocSet other) Returns true if these sets have any elements in common
void	invalidateSize() The number of set bits - size - is cached.
DocIterator	iterator() DocIterator using nextSetBit() public DocIterator iterator() { return new DocIterator() { int pos=bits.nextSetBit(0); public boolean hasNext() { return pos>=0; } public Integer next() { return nextDoc(); } public void remove() { bits.clear(pos); } public int nextDoc() { int old=pos; pos=bits.nextSetBit(old+1); return old; } public float score() { return 0.0f; } }; }
long	memSize() Returns the approximate amount of memory taken by this DocSet.
int	size() Returns the number of documents in the set.
static FixedBitSet	toBitSet(DocSet set)
DocSet	union(DocSet other) Returns the union of this set with another set.
int	unionSize(DocSet other) Returns the number of documents of the union of this set with another set.

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BitDocSet

public BitDocSet()

BitDocSet

public BitDocSet(FixedBitSet bits)

Construct a BitDocSet. The capacity of the FixedBitSet should be at least maxDoc()

BitDocSet

public BitDocSet(FixedBitSet bits,
                 int size)

Construct a BitDocSet, and provides the number of set bits. The capacity of the FixedBitSet should be at least maxDoc()

Method Detail

iterator

public DocIterator iterator()

DocIterator using nextSetBit() public DocIterator iterator() { return new DocIterator() { int pos=bits.nextSetBit(0); public boolean hasNext() { return pos>=0; } public Integer next() { return nextDoc(); } public void remove() { bits.clear(pos); } public int nextDoc() { int old=pos; pos=bits.nextSetBit(old+1); return old; } public float score() { return 0.0f; } }; }

getBits

public FixedBitSet getBits()

Return a FixedBitSet with a bit set for every document in this DocSet. The default implementation iterates on all docs and sets the relevant bits. You should override if you can provide a more efficient implementation.

Returns:

the internal FixedBitSet that should not be modified.

add

public void add(int doc)

Description copied from interface: DocSet

Adds the specified document if it is not currently in the DocSet (optional operation).

Specified by:

add in interface DocSet

See Also:

DocSet.addUnique(int)

addUnique

public void addUnique(int doc)

Description copied from interface: DocSet

Adds a document the caller knows is not currently in the DocSet (optional operation).

This method may be faster then add(doc) in some implementaions provided the caller is certain of the precondition.

Specified by:

addUnique in interface DocSet

See Also:

DocSet.add(int)

size

public int size()

Description copied from interface: DocSet

Returns the number of documents in the set.

invalidateSize

public void invalidateSize()

The number of set bits - size - is cached. If the bitset is changed externally, this method should be used to invalidate the previously cached size.

exists

public boolean exists(int doc)

Returns true of the doc exists in the set. Should only be called when doc < FixedBitSet.length().

intersectionSize

public int intersectionSize(DocSet other)

Description copied from interface: DocSet

Returns the number of documents of the intersection of this set with another set. May be more efficient than actually creating the intersection and then getting it's size.

Specified by:

intersectionSize in interface DocSet

intersects

public boolean intersects(DocSet other)

Description copied from interface: DocSet

Returns true if these sets have any elements in common

Specified by:

intersects in interface DocSet

unionSize

public int unionSize(DocSet other)

Description copied from interface: DocSet

Returns the number of documents of the union of this set with another set. May be more efficient than actually creating the union and then getting it's size.

Specified by:

unionSize in interface DocSet

andNotSize

public int andNotSize(DocSet other)

Description copied from interface: DocSet

Returns the number of documents in this set that are not in the other set.

Specified by:

andNotSize in interface DocSet

addAllTo

public void addAllTo(DocSet target)

Description copied from interface: DocSet

Adds all the docs from this set to the target set. The target should be sized large enough to accommodate all of the documents before calling this method.

Specified by:

addAllTo in interface DocSet

andNot

public DocSet andNot(DocSet other)

Description copied from interface: DocSet

Returns the documents in this set that are not in the other set. Neither set is modified - a new DocSet is created and returned.

Specified by:

andNot in interface DocSet

Returns:

a DocSet representing this AND NOT other

union

public DocSet union(DocSet other)

Description copied from interface: DocSet

Returns the union of this set with another set. Neither set is modified - a new DocSet is created and returned.

Specified by:

union in interface DocSet

Returns:

a DocSet representing the union

memSize

public long memSize()

Description copied from interface: DocSet

Returns the approximate amount of memory taken by this DocSet. This is only an approximation and doesn't take into account java object overhead.

Returns:

the approximate memory consumption in bytes

clone

protected BitDocSet clone()

Overrides:

clone in class Object

getTopFilter

public Filter getTopFilter()

Description copied from interface: DocSet

Returns a Filter for use in Lucene search methods, assuming this DocSet was generated from the top-level MultiReader that the Lucene search methods will be invoked with.

Specified by:

getTopFilter in interface DocSet

toBitSet

public static FixedBitSet toBitSet(DocSet set)

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

intersection

public DocSet intersection(DocSet other)

Description copied from interface: DocSet

Returns the intersection of this set with another set. Neither set is modified - a new DocSet is created and returned.

Specified by:

intersection in interface DocSet

Returns:

a DocSet representing the intersection