Class MultiDocsEnum

Exposes DocsEnum, merged from DocsEnum API of sub-segments.

Note

This API is experimental and might change in incompatible ways in the next release.

Inheritance
object
DocIdSetIterator
DocsEnum
MultiDocsEnum
Inherited Members
Namespace: Lucene.Net.Index
Assembly: Lucene.Net.dll
Syntax
public sealed class MultiDocsEnum : DocsEnum

Constructors

MultiDocsEnum(MultiTermsEnum, int)

Sole constructor

Declaration
public MultiDocsEnum(MultiTermsEnum parent, int subReaderCount)
Parameters
Type Name Description
MultiTermsEnum parent

The MultiTermsEnum that created us.
int subReaderCount

How many sub-readers are being merged.

Properties

DocID

Returns the following:

@since 2.9

Declaration
public override int DocID { get; }
Property Value
Type Description
int
Overrides

Freq

Returns term frequency in the current document, or 1 if the field was indexed with DOCS_ONLY. Do not call this before NextDoc() is first called, nor after NextDoc() returns NO_MORE_DOCS.

NOTE: if the DocsEnum was obtain with NONE, the result of this method is undefined.
Declaration
public override int Freq { get; }
Property Value
Type Description
int
Overrides

NumSubs

How many sub-readers we are merging.

Declaration
public int NumSubs { get; }
Property Value
Type Description
int
See Also

Subs

Returns sub-readers we are merging.

Declaration
public MultiDocsEnum.EnumWithSlice[] Subs { get; }
Property Value
Type Description
EnumWithSlice[]

Methods

Advance(int)

Advances to the first beyond the current whose document number is greater than or equal to target, and returns the document number itself. Exhausts the iterator and returns NO_MORE_DOCS if target is greater than the highest document number in the set.

The behavior of this method is undefined when called with target <= current, or after the iterator has exhausted. Both cases may result in unpredicted behavior.

When target > current it behaves as if written: 
int Advance(int target) 
{
    int doc;
    while ((doc = NextDoc()) < target) 
    {
    }
    return doc;
}

Some implementations are considerably more efficient than that.

NOTE: this method may be called with NO_MORE_DOCS for efficiency by some Scorers. If your implementation cannot efficiently determine that it should exhaust, it is recommended that you check for that value in each call to this method.

@since 2.9

Declaration
public override int Advance(int target)
Parameters
Type Name Description
int target
Returns
Type Description
int
Overrides

CanReuse(MultiTermsEnum)

Returns true if this instance can be reused by the provided MultiTermsEnum.

Declaration
public bool CanReuse(MultiTermsEnum parent)
Parameters
Type Name Description
MultiTermsEnum parent
Returns
Type Description
bool

GetCost()

Returns the estimated cost of this DocIdSetIterator.

This is generally an upper bound of the number of documents this iterator might match, but may be a rough heuristic, hardcoded value, or otherwise completely inaccurate.
Declaration
public override long GetCost()
Returns
Type Description
long
Overrides

NextDoc()

Advances to the next document in the set and returns the doc it is currently on, or NO_MORE_DOCS if there are no more docs in the set.

NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.

@since 2.9
Declaration
public override int NextDoc()
Returns
Type Description
int
Overrides

ToString()

Returns a string that represents the current object.

Declaration
public override string ToString()
Returns
Type Description
string

A string that represents the current object.
Overrides