org.apache.solr.search

Class HashDocSet

java.lang.Object

org.apache.solr.search.HashDocSet

All Implemented Interfaces:

DocSet

public final class HashDocSet
extends Object

HashDocSet represents an unordered set of Lucene Document Ids using a primitive int hash table. It can be a better choice if there are few docs in the set because it takes up less memory and is faster to iterate and take set intersections.

Since:

solr 0.9

Constructor Summary

Constructors

Constructor and Description
HashDocSet(HashDocSet set)
HashDocSet(int[] docs, int offset, int len) Create a HashDocSet from a list of *unique* ids
HashDocSet(int[] docs, int offset, int len, float inverseLoadFactor) Create a HashDocSet from a list of *unique* ids

Method Summary

Methods

Modifier and Type	Method and Description
void	add(int doc) Adds the specified document if it is not currently in the DocSet (optional operation).
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 HashDocSet	clone()
boolean	equals(Object obj)
boolean	exists(int doc) Returns true if a document is in the DocSet.
OpenBitSet	getBits() Inefficient base implementation.
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
DocIterator	iterator() Returns an iterator that may be used to iterate over all of the documents in the set.
long	memSize() Returns the approximate amount of memory taken by this DocSet.
void	setBitsOn(OpenBitSet target) Takes the docs from this set and sets those bits on the target OpenBitSet.
int	size() Returns the number of documents in the 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

HashDocSet

public HashDocSet(HashDocSet set)

HashDocSet

public HashDocSet(int[] docs,
          int offset,
          int len)

Create a HashDocSet from a list of *unique* ids

HashDocSet

public HashDocSet(int[] docs,
          int offset,
          int len,
          float inverseLoadFactor)

Create a HashDocSet from a list of *unique* ids

Method Detail

exists

public boolean exists(int doc)

Description copied from interface: DocSet

Returns true if a document is in the DocSet.

size

public int size()

Description copied from interface: DocSet

Returns the number of documents in the set.

iterator

public DocIterator iterator()

Description copied from interface: DocSet

Returns an iterator that may be used to iterate over all of the documents in the set.

The order of the documents returned by this iterator is non-deterministic, and any scoring information is meaningless

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

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

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

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

clone

protected HashDocSet clone()

Overrides:

clone in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

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

Throws:

SolrException - Base implementation does not allow modifications

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

Throws:

SolrException - Base implementation does not allow modifications

See Also:

DocSet.add(int)

getBits

public OpenBitSet getBits()

Inefficient base implementation.

Specified by:

getBits in interface DocSet

Returns:

An OpenBitSet with the bit number of every docid set in the set.

See Also:

BitDocSet.getBits()

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

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

setBitsOn

public void setBitsOn(OpenBitSet target)

Description copied from interface: DocSet

Takes the docs from this set and sets those bits on the target OpenBitSet. The target should be sized large enough to accommodate all of the documents before calling this method.

Specified by:

setBitsOn in interface DocSet