Class SortField
Stores information about how to sort documents by terms in an individual field. Fields must be indexed in order to sort by them.
Created: Feb 11, 2004 1:25:29 PM
@since lucene 1.4
Inheritance
Inherited Members
Namespace: Lucene.Net.Search
Assembly: Lucene.Net.dll
Syntax
public class SortField
Constructors
| Improve this Doc View SourceSortField(String, FieldCache.IParser)
Creates a sort by terms in the given field, parsed to numeric values using a custom FieldCache.IParser.
Declaration
public SortField(string field, FieldCache.IParser parser)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by. Must not be |
FieldCache.IParser | parser | Instance of a FieldCache.IParser, which must subclass one of the existing numeric parsers from IFieldCache. Sort type is inferred by testing which numeric parser the parser subclasses. |
Exceptions
Type | Condition |
---|---|
System.ArgumentException | if the parser fails to
subclass an existing numeric parser, or field is |
SortField(String, FieldCache.IParser, Boolean)
Creates a sort, possibly in reverse, by terms in the given field, parsed to numeric values using a custom FieldCache.IParser.
Declaration
public SortField(string field, FieldCache.IParser parser, bool reverse)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by. Must not be |
FieldCache.IParser | parser | Instance of a FieldCache.IParser, which must subclass one of the existing numeric parsers from IFieldCache. Sort type is inferred by testing which numeric parser the parser subclasses. |
System.Boolean | reverse |
|
Exceptions
Type | Condition |
---|---|
System.ArgumentException | if the parser fails to
subclass an existing numeric parser, or field is |
SortField(String, FieldComparerSource)
Creates a sort with a custom comparison function.
Declaration
public SortField(string field, FieldComparerSource comparer)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by; cannot be |
FieldComparerSource | comparer | Returns a comparer for sorting hits. |
SortField(String, FieldComparerSource, Boolean)
Creates a sort, possibly in reverse, with a custom comparison function.
Declaration
public SortField(string field, FieldComparerSource comparer, bool reverse)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by; cannot be |
FieldComparerSource | comparer | Returns a comparer for sorting hits. |
System.Boolean | reverse |
|
SortField(String, SortFieldType)
Creates a sort by terms in the given field with the type of term values explicitly given.
Declaration
public SortField(string field, SortFieldType type)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by. Can be |
SortFieldType | type | Type of values in the terms. |
SortField(String, SortFieldType, Boolean)
Creates a sort, possibly in reverse, by terms in the given field with the type of term values explicitly given.
Declaration
public SortField(string field, SortFieldType type, bool reverse)
Parameters
Type | Name | Description |
---|---|---|
System.String | field | Name of field to sort by. Can be |
SortFieldType | type | Type of values in the terms. |
System.Boolean | reverse |
|
Fields
| Improve this Doc View SourceFIELD_DOC
Represents sorting by document number (index order).
Declaration
public static readonly SortField FIELD_DOC
Field Value
Type | Description |
---|---|
SortField |
FIELD_SCORE
Represents sorting by document score (relevance).
Declaration
public static readonly SortField FIELD_SCORE
Field Value
Type | Description |
---|---|
SortField |
m_missingValue
Declaration
protected object m_missingValue
Field Value
Type | Description |
---|---|
System.Object |
STRING_FIRST
Pass this to MissingValue to have missing string values sort first.
Declaration
public static readonly object STRING_FIRST
Field Value
Type | Description |
---|---|
System.Object |
STRING_LAST
Pass this to MissingValue to have missing string values sort last.
Declaration
public static readonly object STRING_LAST
Field Value
Type | Description |
---|---|
System.Object |
Properties
| Improve this Doc View SourceBytesComparer
Declaration
public virtual IComparer<BytesRef> BytesComparer { get; set; }
Property Value
Type | Description |
---|---|
System.Collections.Generic.IComparer<BytesRef> |
ComparerSource
Returns the FieldComparerSource used for custom sorting.
Declaration
public virtual FieldComparerSource ComparerSource { get; }
Property Value
Type | Description |
---|---|
FieldComparerSource |
Field
Declaration
public virtual string Field { get; }
Property Value
Type | Description |
---|---|
System.String | Name of field, possibly |
IsReverse
Returns whether the sort should be reversed.
Declaration
public virtual bool IsReverse { get; }
Property Value
Type | Description |
---|---|
System.Boolean |
|
MissingValue
Declaration
public object MissingValue { get; }
Property Value
Type | Description |
---|---|
System.Object |
NeedsScores
Whether the relevance score is needed to sort documents.
Declaration
public virtual bool NeedsScores { get; }
Property Value
Type | Description |
---|---|
System.Boolean |
Parser
Returns the instance of a IFieldCache parser that fits to the given sort type.
May return null
if no parser was specified. Sorting is using the default parser then.
Declaration
public virtual FieldCache.IParser Parser { get; }
Property Value
Type | Description |
---|---|
FieldCache.IParser | An instance of a IFieldCache parser, or |
Type
Returns the type of contents in the field.
Declaration
public virtual SortFieldType Type { get; }
Property Value
Type | Description |
---|---|
SortFieldType |
Methods
| Improve this Doc View SourceEquals(Object)
Returns true
if o
is equal to this. If a
FieldComparerSource or
FieldCache.IParser was provided, it must properly
implement equals (unless a singleton is always used).
Declaration
public override bool Equals(object o)
Parameters
Type | Name | Description |
---|---|---|
System.Object | o |
Returns
Type | Description |
---|---|
System.Boolean |
Overrides
GetComparer(Int32, Int32)
Returns the FieldComparer to use for sorting.
Note
This API is experimental and might change in incompatible ways in the next release.
Declaration
public virtual FieldComparer GetComparer(int numHits, int sortPos)
Parameters
Type | Name | Description |
---|---|---|
System.Int32 | numHits | Number of top hits the queue will store |
System.Int32 | sortPos | Position of this SortField within Sort. The comparer is primary if sortPos==0, secondary if sortPos==1, etc. Some comparers can optimize themselves when they are the primary sort. |
Returns
Type | Description |
---|---|
FieldComparer | FieldComparer to use when sorting |
GetHashCode()
Returns a hash code value for this object. If a FieldComparerSource or FieldCache.IParser was provided, it must properly implement GetHashCode() (unless a singleton is always used).
Declaration
public override int GetHashCode()
Returns
Type | Description |
---|---|
System.Int32 |
Overrides
Rewrite(IndexSearcher)
Rewrites this SortField, returning a new SortField if a change is made. Subclasses should override this define their rewriting behavior when this SortField is of type REWRITEABLE.
Note
This API is experimental and might change in incompatible ways in the next release.
Declaration
public virtual SortField Rewrite(IndexSearcher searcher)
Parameters
Type | Name | Description |
---|---|---|
IndexSearcher | searcher | IndexSearcher to use during rewriting |
Returns
Type | Description |
---|---|
SortField | New rewritten SortField, or |
Exceptions
Type | Condition |
---|---|
System.IO.IOException | Can be thrown by the rewriting |
SetMissingValue(Byte)
Declaration
[Obsolete]
public void SetMissingValue(byte value)
Parameters
Type | Name | Description |
---|---|---|
System.Byte | value |
SetMissingValue(Double)
Declaration
public void SetMissingValue(double value)
Parameters
Type | Name | Description |
---|---|---|
System.Double | value |
SetMissingValue(Int16)
Declaration
[Obsolete]
public void SetMissingValue(short value)
Parameters
Type | Name | Description |
---|---|---|
System.Int16 | value |
SetMissingValue(Int32)
Declaration
public void SetMissingValue(int value)
Parameters
Type | Name | Description |
---|---|---|
System.Int32 | value |
SetMissingValue(Int64)
Declaration
public void SetMissingValue(long value)
Parameters
Type | Name | Description |
---|---|---|
System.Int64 | value |
SetMissingValue(Object)
Declaration
public virtual void SetMissingValue(object value)
Parameters
Type | Name | Description |
---|---|---|
System.Object | value |
SetMissingValue(SByte)
Declaration
[CLSCompliant(false)]
[Obsolete]
public void SetMissingValue(sbyte value)
Parameters
Type | Name | Description |
---|---|---|
System.SByte | value |
SetMissingValue(Single)
Declaration
public void SetMissingValue(float value)
Parameters
Type | Name | Description |
---|---|---|
System.Single | value |
ToString()
Declaration
public override string ToString()
Returns
Type | Description |
---|---|
System.String |