--- /dev/null
+package org.apache.lucene.search;
+/**
+ * Copyright 2007 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.search.spans.SpanQuery;
+import org.apache.lucene.search.spans.Spans;
+import org.apache.lucene.util.FixedBitSet;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Constrains search results to only match those which also match a provided
+ * query. Also provides position information about where each document matches
+ * at the cost of extra space compared with the QueryWrapperFilter.
+ * There is an added cost to this above what is stored in a {@link QueryWrapperFilter}. Namely,
+ * the position information for each matching document is stored.
+ * <p/>
+ * This filter does not cache. See the {@link org.apache.lucene.search.CachingSpanFilter} for a wrapper that
+ * caches.
+ */
+public class SpanQueryFilter extends SpanFilter {
+ protected SpanQuery query;
+
+ protected SpanQueryFilter()
+ {
+
+ }
+
+ /** Constructs a filter which only matches documents matching
+ * <code>query</code>.
+ * @param query The {@link org.apache.lucene.search.spans.SpanQuery} to use as the basis for the Filter.
+ */
+ public SpanQueryFilter(SpanQuery query) {
+ this.query = query;
+ }
+
+ @Override
+ public DocIdSet getDocIdSet(IndexReader reader) throws IOException {
+ SpanFilterResult result = bitSpans(reader);
+ return result.getDocIdSet();
+ }
+
+ @Override
+ public SpanFilterResult bitSpans(IndexReader reader) throws IOException {
+
+ final FixedBitSet bits = new FixedBitSet(reader.maxDoc());
+ Spans spans = query.getSpans(reader);
+ List<SpanFilterResult.PositionInfo> tmp = new ArrayList<SpanFilterResult.PositionInfo>(20);
+ int currentDoc = -1;
+ SpanFilterResult.PositionInfo currentInfo = null;
+ while (spans.next())
+ {
+ int doc = spans.doc();
+ bits.set(doc);
+ if (currentDoc != doc)
+ {
+ currentInfo = new SpanFilterResult.PositionInfo(doc);
+ tmp.add(currentInfo);
+ currentDoc = doc;
+ }
+ currentInfo.addPosition(spans.start(), spans.end());
+ }
+ return new SpanFilterResult(bits, tmp);
+ }
+
+
+ public SpanQuery getQuery() {
+ return query;
+ }
+
+ @Override
+ public String toString() {
+ return "SpanQueryFilter(" + query + ")";
+ }
+
+ @Override
+ public boolean equals(Object o) {
+ return o instanceof SpanQueryFilter && this.query.equals(((SpanQueryFilter) o).query);
+ }
+
+ @Override
+ public int hashCode() {
+ return query.hashCode() ^ 0x923F64B9;
+ }
+}