org.apache.solr.highlight

Class PostingsSolrHighlighter

java.lang.Object

org.apache.solr.highlight.SolrHighlighter

org.apache.solr.highlight.PostingsSolrHighlighter

All Implemented Interfaces:

PluginInfoInitialized

public class PostingsSolrHighlighter
extends SolrHighlighter
implements PluginInfoInitialized

Highlighter impl that uses PostingsHighlighter

Example configuration:

   <requestHandler name="/select" class="solr.SearchHandler">
     <lst name="defaults">
       <str name="hl.method">postings</str>
       <int name="hl.snippets">1</int>
       <str name="hl.tag.pre">&lt;em&gt;</str>
       <str name="hl.tag.post">&lt;/em&gt;</str>
       <str name="hl.tag.ellipsis">... </str>
       <bool name="hl.defaultSummary">true</bool>
       <str name="hl.encoder">simple</str>
       <float name="hl.score.k1">1.2</float>
       <float name="hl.score.b">0.75</float>
       <float name="hl.score.pivot">87</float>
       <str name="hl.bs.language"></str>
       <str name="hl.bs.country"></str>
       <str name="hl.bs.variant"></str>
       <str name="hl.bs.type">SENTENCE</str>
       <int name="hl.maxAnalyzedChars">10000</int>
       <str name="hl.multiValuedSeparatorChar"> </str>
       <bool name="hl.highlightMultiTerm">false</bool>
     </lst>
   </requestHandler>
 

Notes:

• fields to highlight must be configured with storeOffsetsWithPositions="true"
• hl.q (string) can specify the query
• hl.fl (string) specifies the field list.
• hl.snippets (int) specifies how many underlying passages form the resulting snippet.
• hl.tag.pre (string) specifies text which appears before a highlighted term.
• hl.tag.post (string) specifies text which appears after a highlighted term.
• hl.tag.ellipsis (string) specifies text which joins non-adjacent passages.
• hl.defaultSummary (bool) specifies if a field should have a default summary.
• hl.encoder (string) can be 'html' (html escapes content) or 'simple' (no escaping).
• hl.score.k1 (float) specifies bm25 scoring parameter 'k1'
• hl.score.b (float) specifies bm25 scoring parameter 'b'
• hl.score.pivot (float) specifies bm25 scoring parameter 'avgdl'
• hl.bs.type (string) specifies how to divide text into passages: [SENTENCE, LINE, WORD, CHAR, WHOLE]
• hl.bs.language (string) specifies language code for BreakIterator. default is empty string (root locale)
• hl.bs.country (string) specifies country code for BreakIterator. default is empty string (root locale)
• hl.bs.variant (string) specifies country code for BreakIterator. default is empty string (root locale)
• hl.maxAnalyzedChars specifies how many characters at most will be processed in a document.
• hl.multiValuedSeparatorChar specifies the logical separator between values for multi-valued fields.
• hl.highlightMultiTerm enables highlighting for range/wildcard/fuzzy/prefix queries. NOTE: currently hl.maxAnalyzedChars cannot yet be specified per-field

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

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	PostingsSolrHighlighter.SolrExtendedPostingsHighlighter From getHighlighter(org.apache.solr.request.SolrQueryRequest).

Field Summary

Fields inherited from class org.apache.solr.highlight.SolrHighlighter

DEFAULT_PHRASE_LIMIT

Constructor Summary

Constructors

Constructor and Description
PostingsSolrHighlighter()

Method Summary

Modifier and Type	Method and Description
NamedList<Object>	doHighlighting(DocList docs, Query query, SolrQueryRequest req, String[] defaultFields) Generates a list of Highlighted query fragments for each item in a list of documents, or returns null if highlighting is disabled.
protected NamedList<Object>	encodeSnippets(String[] keys, String[] fieldNames, Map<String,String[]> snippets) Encodes the resulting snippets into a namedlist
protected PostingsHighlighter	getHighlighter(SolrQueryRequest req) Creates an instance of the Lucene PostingsHighlighter.
protected String[]	getUniqueKeys(SolrIndexSearcher searcher, int[] docIDs) Retrieves the unique keys for the topdocs to key the results
void	init(PluginInfo info)
protected BreakIterator	parseBreakIterator(String type, Locale locale) parse a break iterator type for the specified locale
protected Locale	parseLocale(String language, String country, String variant) parse a locale from a language+country+variant spec
protected int[]	toDocIDs(DocList docs) Converts solr's DocList to the int[] docIDs

Methods inherited from class org.apache.solr.highlight.SolrHighlighter

emptyArray, getHighlightFields, isHighlightingEnabled

Methods inherited from class java.lang.Object

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

Constructor Detail

PostingsSolrHighlighter

public PostingsSolrHighlighter()

Method Detail

init

public void init(PluginInfo info)

Specified by:

init in interface PluginInfoInitialized

doHighlighting

public NamedList<Object> doHighlighting(DocList docs,
                                        Query query,
                                        SolrQueryRequest req,
                                        String[] defaultFields)
                                 throws IOException

Description copied from class: SolrHighlighter

Generates a list of Highlighted query fragments for each item in a list of documents, or returns null if highlighting is disabled.

Specified by:

doHighlighting in class SolrHighlighter

Parameters:

docs - query results

query - the query

req - the current request

defaultFields - default list of fields to summarize

Returns:

NamedList containing a NamedList for each document, which in turns contains sets (field, summary) pairs.

Throws:

IOException

getHighlighter

protected PostingsHighlighter getHighlighter(SolrQueryRequest req)

Creates an instance of the Lucene PostingsHighlighter. Provided for subclass extension so that a subclass can return a subclass of PostingsSolrHighlighter.SolrExtendedPostingsHighlighter.

encodeSnippets

protected NamedList<Object> encodeSnippets(String[] keys,
                                           String[] fieldNames,
                                           Map<String,String[]> snippets)

Encodes the resulting snippets into a namedlist

Parameters:

keys - the document unique keys

fieldNames - field names to highlight in the order

snippets - map from field name to snippet array for the docs

Returns:

encoded namedlist of summaries

toDocIDs

protected int[] toDocIDs(DocList docs)

Converts solr's DocList to the int[] docIDs

getUniqueKeys

protected String[] getUniqueKeys(SolrIndexSearcher searcher,
                                 int[] docIDs)
                          throws IOException

Retrieves the unique keys for the topdocs to key the results

Throws:

IOException

parseBreakIterator

protected BreakIterator parseBreakIterator(String type,
                                           Locale locale)

parse a break iterator type for the specified locale

parseLocale

protected Locale parseLocale(String language,
                             String country,
                             String variant)

parse a locale from a language+country+variant spec