org.apache.solr.schema

Class RandomSortField

java.lang.Object

org.apache.solr.schema.FieldProperties

org.apache.solr.schema.FieldType

org.apache.solr.schema.RandomSortField

public class RandomSortField
extends FieldType

Utility Field used for random sorting. It should not be passed a value.

This random sorting implementation uses the dynamic field name to set the random 'seed'. To get random sorting order, you need to use a random dynamic field name. For example, you will need to configure schema.xml:

 <types>
  ...
  <fieldType name="random" class="solr.RandomSortField" />
  ... 
 </types>
 <fields>
  ...
  <dynamicField name="random*" type="random" indexed="true" stored="false"/>
  ...
 </fields>
 

Examples of queries:

• http://localhost:8983/solr/select/?q=*:*&fl=name&sort=random_1234%20desc
• http://localhost:8983/solr/select/?q=*:*&fl=name&sort=random_2345%20desc
• http://localhost:8983/solr/select/?q=*:*&fl=name&sort=random_ABDC%20desc
• http://localhost:8983/solr/select/?q=*:*&fl=name&sort=random_21%20desc

Note that multiple calls to the same URL will return the same sorting order.

Since:

solr 1.3

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RandomSortField.RandomValueSource

Nested classes/interfaces inherited from class org.apache.solr.schema.FieldType

FieldType.DefaultAnalyzer, FieldType.MultiValueSelector

Field Summary

Fields inherited from class org.apache.solr.schema.FieldType

ANALYZER, args, AUTO_GENERATE_PHRASE_QUERIES, CHAR_FILTER, CHAR_FILTERS, CLASS_NAME, docValuesFormat, ENABLE_GRAPH_QUERIES, falseProperties, FILTER, FILTERS, INDEX, INDEX_ANALYZER, MULTI_TERM, MULTI_TERM_ANALYZER, POLY_FIELD_SEPARATOR, postingsFormat, properties, QUERY, QUERY_ANALYZER, similarity, SIMILARITY, similarityFactory, SYNONYM_QUERY_STYLE, TOKENIZER, trueProperties, TYPE, TYPE_NAME, typeName

Fields inherited from class org.apache.solr.schema.FieldProperties

BINARY, DOC_VALUES, INDEXED, LARGE_FIELD, MULTIVALUED, OMIT_NORMS, OMIT_POSITIONS, OMIT_TF_POSITIONS, REQUIRED, SORT_MISSING_FIRST, SORT_MISSING_LAST, STORE_OFFSETS, STORE_TERMOFFSETS, STORE_TERMPAYLOADS, STORE_TERMPOSITIONS, STORE_TERMVECTORS, STORED, TOKENIZED, UNINVERTIBLE, USE_DOCVALUES_AS_STORED

Constructor Summary

Constructors

Constructor and Description
RandomSortField()

Method Summary

Modifier and Type	Method and Description
SortField	getSortField(SchemaField field, boolean reverse) Returns the SortField instance that should be used to sort fields of this type.
UninvertingReader.Type	getUninversionType(SchemaField sf) If DocValues is not enabled for a field, but it's indexed, docvalues can be constructed on the fly (uninverted, aka fieldcache) on the first request to sort, facet, etc.
ValueSource	getValueSource(SchemaField field, QParser qparser) called to get the default value source (normally, from the Lucene FieldCache.)
void	write(TextResponseWriter writer, String name, IndexableField f) calls back to TextResponseWriter to write the field value

Methods inherited from class org.apache.solr.schema.FieldType

checkSchemaField, checkSupportsDocValues, createField, createField, createFields, getAnalyzerProperties, getClassArg, getDefaultMultiValueSelectorForSort, getDocValuesFormat, getFieldQuery, getIndexAnalyzer, getNamedPropertyValues, getNonFieldPropertyArgs, getNumberType, getNumericSort, getPostingsFormat, getPrefixQuery, getQueryAnalyzer, getRangeQuery, getRewriteMethod, getSetQuery, getSimilarity, getSimilarityFactory, getSingleValueSource, getSortedNumericSortField, getSortedSetSortField, getSortField, getStringSort, getTypeName, hasProperty, indexedToReadable, indexedToReadable, init, isExplicitAnalyzer, isExplicitQueryAnalyzer, isMultiValued, isPointField, isPolyField, isTokenized, isUtf8Field, marshalBase64SortValue, marshalSortValue, marshalStringSortValue, multiValuedFieldCache, readableToIndexed, readableToIndexed, restrictProps, setArgs, setIndexAnalyzer, setIsExplicitAnalyzer, setIsExplicitQueryAnalyzer, setQueryAnalyzer, setSimilarity, storedToIndexed, storedToReadable, supportsAnalyzers, toExternal, toInternal, toNativeType, toObject, toObject, toString, unmarshalBase64SortValue, unmarshalSortValue, unmarshalStringSortValue, useDocValuesAsStored, write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RandomSortField

public RandomSortField()

Method Detail

getSortField

public SortField getSortField(SchemaField field,
                              boolean reverse)

Description copied from class: FieldType

Returns the SortField instance that should be used to sort fields of this type.

Specified by:

getSortField in class FieldType

See Also:

SchemaField.checkSortability(), FieldType.getStringSort(org.apache.solr.schema.SchemaField, boolean), FieldType.getNumericSort(org.apache.solr.schema.SchemaField, org.apache.solr.schema.NumberType, boolean)

getUninversionType

public UninvertingReader.Type getUninversionType(SchemaField sf)

Description copied from class: FieldType

If DocValues is not enabled for a field, but it's indexed, docvalues can be constructed on the fly (uninverted, aka fieldcache) on the first request to sort, facet, etc. This specifies the structure to use.

This method will not be used if the field is (effectively) uninvertible="false"

Specified by:

getUninversionType in class FieldType

Parameters:

sf - field instance

Returns:

type to uninvert, or null (to disallow uninversion for the field)

See Also:

SchemaField.isUninvertible()

getValueSource

public ValueSource getValueSource(SchemaField field,
                                  QParser qparser)

Description copied from class: FieldType

called to get the default value source (normally, from the Lucene FieldCache.)

Overrides:

getValueSource in class FieldType

write

public void write(TextResponseWriter writer,
                  String name,
                  IndexableField f)
           throws IOException

Description copied from class: FieldType

calls back to TextResponseWriter to write the field value

Specified by:

write in class FieldType

Throws:

IOException