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The Adobe Experience Manager SDK

There is a newer version: 2024.11.18751.20241128T090041Z-241100






The calculus of spans.

A span is a <doc,startPosition,endPosition> tuple.

The following span query operators are implemented:



A {@link org.apache.lucene.search.spans.SpanTermQuery SpanTermQuery} matches all spans
containing a particular {@link org.apache.lucene.index.Term Term}.

 A {@link org.apache.lucene.search.spans.SpanNearQuery SpanNearQuery} matches spans
which occur near one another, and can be used to implement things like
phrase search (when constructed from {@link org.apache.lucene.search.spans.SpanTermQuery}s)
and inter-phrase proximity (when constructed from other {@link org.apache.lucene.search.spans.SpanNearQuery}s).

A {@link org.apache.lucene.search.spans.SpanOrQuery SpanOrQuery} merges spans from a
number of other {@link org.apache.lucene.search.spans.SpanQuery}s.

A {@link org.apache.lucene.search.spans.SpanNotQuery SpanNotQuery} removes spans
matching one {@link org.apache.lucene.search.spans.SpanQuery SpanQuery} which overlap (or comes
near) another.  This can be used, e.g., to implement within-paragraph
search.

A {@link org.apache.lucene.search.spans.SpanFirstQuery SpanFirstQuery} matches spans
matching q whose end position is less than
n.  This can be used to constrain matches to the first
part of the document.

A {@link org.apache.lucene.search.spans.SpanPositionRangeQuery SpanPositionRangeQuery} is
a more general form of SpanFirstQuery that can constrain matches to arbitrary portions of the document.



In all cases, output spans are minimally inclusive.  In other words, a
span formed by matching a span in x and y starts at the lesser of the
two starts and ends at the greater of the two ends.


For example, a span query which matches "John Kerry" within ten
words of "George Bush" within the first 100 words of the document
could be constructed with:
SpanQuery john   = new SpanTermQuery(new Term("content", "john"));
SpanQuery kerry  = new SpanTermQuery(new Term("content", "kerry"));
SpanQuery george = new SpanTermQuery(new Term("content", "george"));
SpanQuery bush   = new SpanTermQuery(new Term("content", "bush"));

SpanQuery johnKerry =
   new SpanNearQuery(new SpanQuery[] {john, kerry}, 0, true);

SpanQuery georgeBush =
   new SpanNearQuery(new SpanQuery[] {george, bush}, 0, true);

SpanQuery johnKerryNearGeorgeBush =
   new SpanNearQuery(new SpanQuery[] {johnKerry, georgeBush}, 10, false);

SpanQuery johnKerryNearGeorgeBushAtStart =
   new SpanFirstQuery(johnKerryNearGeorgeBush, 100);


Span queries may be freely intermixed with other Lucene queries.
So, for example, the above query can be restricted to documents which
also use the word "iraq" with:

Query query = new BooleanQuery();
query.add(johnKerryNearGeorgeBushAtStart, true, false);
query.add(new TermQuery("content", "iraq"), true, false);