org.apache.jackrabbit.core.query.lucene
Class AbstractExcerpt

java.lang.Object
  org.apache.jackrabbit.core.query.lucene.AbstractExcerpt

All Implemented Interfaces:

ExcerptProvider, HighlightingExcerptProvider

Direct Known Subclasses:

DefaultHTMLExcerpt, DefaultXMLExcerpt, WeightedHTMLExcerpt, WeightedXMLExcerpt

public abstract class AbstractExcerpt
extends Object
implements HighlightingExcerptProvider

AbstractExcerpt implements base functionality for an excerpt provider.

Field Summary

protected SearchIndex	index The search index.
protected org.apache.lucene.search.Query	query The current query.

Fields inherited from interface org.apache.jackrabbit.core.query.lucene.ExcerptProvider

REP_EXCERPT

Constructor Summary

AbstractExcerpt()

Method Summary

protected abstract String	createExcerpt(org.apache.lucene.index.TermPositionVector tpv, String text, int maxFragments, int maxFragmentSize) Creates an excerpt for the given text using token offset information provided by tpv.
String	getExcerpt(NodeId id, int maxFragments, int maxFragmentSize) Returns the XML excerpt for the node with id.
protected Set<org.apache.lucene.index.Term>	getQueryTerms()
String	highlight(String text) Highlights the matching terms in the passed text.
void	init(org.apache.lucene.search.Query query, SearchIndex index) Initializes this excerpt provider.

Methods inherited from class java.lang.Object

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

Field Detail

index

protected SearchIndex index

The search index.

query

protected org.apache.lucene.search.Query query

The current query.

Constructor Detail

AbstractExcerpt

public AbstractExcerpt()

Method Detail

init

public void init(org.apache.lucene.search.Query query,
                 SearchIndex index)
          throws IOException

Initializes this excerpt provider.

Specified by:

init in interface ExcerptProvider

Parameters:

query - excerpts will be based on this query.

index - provides access to the search index.

Throws:

IOException - if an error occurs while initializing this excerpt provider.

getExcerpt

public String getExcerpt(NodeId id,
                         int maxFragments,
                         int maxFragmentSize)
                  throws IOException

Returns the XML excerpt for the node with id.

Specified by:

getExcerpt in interface ExcerptProvider

Parameters:

id - a node id.

maxFragments - the maximum number of fragments to create.

maxFragmentSize - the maximum number of characters in a fragment.

Returns:

the XML excerpt or null if there is no node with id.

Throws:

IOException - if an error occurs while creating the excerpt.

highlight

public String highlight(String text)
                 throws IOException

Highlights the matching terms in the passed text.

Specified by:

highlight in interface HighlightingExcerptProvider

Parameters:

text - the input text.

Returns:

the highlighted text.

Throws:

IOException - if an error occurs while highlighting the text.

createExcerpt

protected abstract String createExcerpt(org.apache.lucene.index.TermPositionVector tpv,
                                        String text,
                                        int maxFragments,
                                        int maxFragmentSize)
                                 throws IOException

Creates an excerpt for the given text using token offset information provided by tpv.

Parameters:

tpv - the term position vector for the fulltext field.

text - the original text.

maxFragments - the maximum number of fragments to create.

maxFragmentSize - the maximum number of characters in a fragment.

Returns:

the xml excerpt.

Throws:

IOException - if an error occurs while creating the excerpt.

getQueryTerms

protected final Set<org.apache.lucene.index.Term> getQueryTerms()

Returns:

the extracted terms from the query.