java.lang.Object
- org.apache.lucene.search.SortField

All Implemented Interfaces:

Serializable
```
public class SortField
extends Object
implements Serializable
```
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

See Also:

Sort, Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`BYTE`	Sort using term values as encoded Bytes.
`static int`	`CUSTOM`	Sort using a custom Comparator.
`static int`	`DOC`	Sort by document number (index order).
`static int`	`DOUBLE`	Sort using term values as encoded Doubles.
`static SortField`	`FIELD_DOC`	Represents sorting by document number (index order).
`static SortField`	`FIELD_SCORE`	Represents sorting by document score (relevance).
`static int`	`FLOAT`	Sort using term values as encoded Floats.
`static int`	`INT`	Sort using term values as encoded Integers.
`static int`	`LONG`	Sort using term values as encoded Longs.
`static int`	`SCORE`	Sort by document score (relevance).
`static int`	`SHORT`	Sort using term values as encoded Shorts.
`static int`	`STRING`	Sort using term values as Strings.
`static int`	`STRING_VAL`	Sort using term values as Strings, but comparing by value (using String.compareTo) for all comparisons.

Constructor Summary

Constructors
Constructor	Description
`SortField(String field, int type)`	Creates a sort by terms in the given field with the type of term values explicitly given.
`SortField(String field, int type, boolean reverse)`	Creates a sort, possibly in reverse, by terms in the given field with the type of term values explicitly given.
`SortField(String field, Locale locale)`	Creates a sort by terms in the given field sorted according to the given locale.
`SortField(String field, Locale locale, boolean reverse)`	Creates a sort, possibly in reverse, by terms in the given field sorted according to the given locale.
`SortField(String field, FieldCache.Parser parser)`	Creates a sort by terms in the given field, parsed to numeric values using a custom `FieldCache.Parser`.
`SortField(String field, FieldCache.Parser parser, boolean reverse)`	Creates a sort, possibly in reverse, by terms in the given field, parsed to numeric values using a custom `FieldCache.Parser`.
`SortField(String field, FieldComparatorSource comparator)`	Creates a sort with a custom comparison function.
`SortField(String field, FieldComparatorSource comparator, boolean reverse)`	Creates a sort, possibly in reverse, with a custom comparison function.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`equals(Object o)`	Returns true if `o` is equal to this.
`FieldComparator<?>`	`getComparator(int numHits, int sortPos)`	Returns the `FieldComparator` to use for sorting.
`FieldComparatorSource`	`getComparatorSource()`	Returns the `FieldComparatorSource` used for custom sorting
`String`	`getField()`	Returns the name of the field.
`Locale`	`getLocale()`	Returns the Locale by which term values are interpreted.
`FieldCache.Parser`	`getParser()`	Returns the instance of a `FieldCache` parser that fits to the given sort type.
`boolean`	`getReverse()`	Returns whether the sort should be reversed.
`int`	`getType()`	Returns the type of contents in the field.
`int`	`hashCode()`	Returns true if `o` is equal to this.
`SortField`	`setMissingValue(Object missingValue)`	Set a default sorting value for documents which lacks one
`String`	`toString()`

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

- Field Detail
  - SCORE
```
public static final int SCORE
```
    Sort by document score (relevance). Sort values are Float and higher values are at the front.
    
    See Also:
    
    Constant Field Values
  - DOC
```
public static final int DOC
```
    Sort by document number (index order). Sort values are Integer and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - STRING
```
public static final int STRING
```
    Sort using term values as Strings. Sort values are String and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - INT
```
public static final int INT
```
    Sort using term values as encoded Integers. Sort values are Integer and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - FLOAT
```
public static final int FLOAT
```
    Sort using term values as encoded Floats. Sort values are Float and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - LONG
```
public static final int LONG
```
    Sort using term values as encoded Longs. Sort values are Long and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - DOUBLE
```
public static final int DOUBLE
```
    Sort using term values as encoded Doubles. Sort values are Double and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - SHORT
```
public static final int SHORT
```
    Sort using term values as encoded Shorts. Sort values are Short and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - CUSTOM
```
public static final int CUSTOM
```
    Sort using a custom Comparator. Sort values are any Comparable and sorting is done according to natural order.
    
    See Also:
    
    Constant Field Values
  - BYTE
```
public static final int BYTE
```
    Sort using term values as encoded Bytes. Sort values are Byte and lower values are at the front.
    
    See Also:
    
    Constant Field Values
  - STRING_VAL
```
public static final int STRING_VAL
```
    Sort using term values as Strings, but comparing by value (using String.compareTo) for all comparisons. This is typically slower than STRING, which uses ordinals to do the sorting.
    
    See Also:
    
    Constant Field Values
  - FIELD_SCORE
```
public static final SortField FIELD_SCORE
```
    Represents sorting by document score (relevance).
  - FIELD_DOC
```
public static final SortField FIELD_DOC
```
    Represents sorting by document number (index order).
- Constructor Detail
  - SortField
```
public SortField(String field,
                 int type)
```
    Creates a sort by terms in the given field with the type of term values explicitly given.
    
    Parameters:
    
    field - Name of field to sort by. Can be null if type is SCORE or DOC.
    
    type - Type of values in the terms.
  - SortField
```
public SortField(String field,
                 int type,
                 boolean reverse)
```
    Creates a sort, possibly in reverse, by terms in the given field with the type of term values explicitly given.
    
    Parameters:
    
    field - Name of field to sort by. Can be null if type is SCORE or DOC.
    
    type - Type of values in the terms.
    
    reverse - True if natural order should be reversed.
  - SortField
```
public SortField(String field,
                 FieldCache.Parser parser)
```
    Creates a sort by terms in the given field, parsed to numeric values using a custom FieldCache.Parser.
    
    Parameters:
    
    field - Name of field to sort by. Must not be null.
    
    parser - Instance of a FieldCache.Parser, which must subclass one of the existing numeric parsers from FieldCache. Sort type is inferred by testing which numeric parser the parser subclasses.
    
    Throws:
    
    IllegalArgumentException - if the parser fails to subclass an existing numeric parser, or field is null
  - SortField
```
public SortField(String field,
                 FieldCache.Parser parser,
                 boolean reverse)
```
    Creates a sort, possibly in reverse, by terms in the given field, parsed to numeric values using a custom FieldCache.Parser.
    
    Parameters:
    
    field - Name of field to sort by. Must not be null.
    
    parser - Instance of a FieldCache.Parser, which must subclass one of the existing numeric parsers from FieldCache. Sort type is inferred by testing which numeric parser the parser subclasses.
    
    reverse - True if natural order should be reversed.
    
    Throws:
    
    IllegalArgumentException - if the parser fails to subclass an existing numeric parser, or field is null
  - SortField
```
public SortField(String field,
                 Locale locale)
```
    Creates a sort by terms in the given field sorted according to the given locale.
    
    Parameters:
    
    field - Name of field to sort by, cannot be null.
    
    locale - Locale of values in the field.
  - SortField
```
public SortField(String field,
                 Locale locale,
                 boolean reverse)
```
    Creates a sort, possibly in reverse, by terms in the given field sorted according to the given locale.
    
    Parameters:
    
    field - Name of field to sort by, cannot be null.
    
    locale - Locale of values in the field.
  - SortField
```
public SortField(String field,
                 FieldComparatorSource comparator)
```
    Creates a sort with a custom comparison function.
    
    Parameters:
    
    field - Name of field to sort by; cannot be null.
    
    comparator - Returns a comparator for sorting hits.
  - SortField
```
public SortField(String field,
                 FieldComparatorSource comparator,
                 boolean reverse)
```
    Creates a sort, possibly in reverse, with a custom comparison function.
    
    Parameters:
    
    field - Name of field to sort by; cannot be null.
    
    comparator - Returns a comparator for sorting hits.
    
    reverse - True if natural order should be reversed.
- Method Detail
  - setMissingValue
```
public SortField setMissingValue(Object missingValue)
```
    Set a default sorting value for documents which lacks one
  - getField
```
public String getField()
```
    Returns the name of the field. Could return null if the sort is by SCORE or DOC.
    
    Returns:
    
    Name of field, possibly null.
  - getType
```
public int getType()
```
    Returns the type of contents in the field.
    
    Returns:
    
    One of the constants SCORE, DOC, STRING, INT or FLOAT.
  - getLocale
```
public Locale getLocale()
```
    Returns the Locale by which term values are interpreted. May return null if no Locale was specified.
    
    Returns:
    
    Locale, or null.
  - getParser
```
public FieldCache.Parser getParser()
```
    Returns the instance of a FieldCache parser that fits to the given sort type. May return null if no parser was specified. Sorting is using the default parser then.
    
    Returns:
    
    An instance of a FieldCache parser, or null.
  - getReverse
```
public boolean getReverse()
```
    Returns whether the sort should be reversed.
    
    Returns:
    
    True if natural order should be reversed.
  - getComparatorSource
```
public FieldComparatorSource getComparatorSource()
```
    Returns the FieldComparatorSource used for custom sorting
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - equals
```
public boolean equals(Object o)
```
    Returns true if o is equal to this. If a FieldComparatorSource or FieldCache.Parser was provided, it must properly implement equals (unless a singleton is always used).
    
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Returns true if o is equal to this. If a FieldComparatorSource or FieldCache.Parser was provided, it must properly implement hashCode (unless a singleton is always used).
    
    Overrides:
    
    hashCode in class Object
  - getComparator
```
public FieldComparator<?> getComparator(int numHits,
                                        int sortPos)
                                 throws IOException
```
    Returns the FieldComparator to use for sorting.
    
    Parameters:
    
    numHits - number of top hits the queue will store
    
    sortPos - position of this SortField within Sort. The comparator is primary if sortPos==0, secondary if sortPos==1, etc. Some comparators can optimize themselves when they are the primary sort.
    
    Returns:
    
    FieldComparator to use when sorting
    
    Throws:
    
    IOException
    
    WARNING: This API is experimental and might change in incompatible ways in the next release.

Class SortField

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SCORE

DOC

STRING

INT

FLOAT

LONG

DOUBLE

SHORT

CUSTOM

BYTE

STRING_VAL

FIELD_SCORE

FIELD_DOC

Constructor Detail

SortField

SortField

SortField

SortField

SortField

SortField

SortField

SortField

Method Detail

setMissingValue

getField

getType

getLocale

getParser

getReverse

getComparatorSource

toString

equals

hashCode

getComparator