X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/FieldMaskingSpanQuery.java?ds=sidebyside diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/FieldMaskingSpanQuery.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/FieldMaskingSpanQuery.java new file mode 100644 index 0000000..f6eeecb --- /dev/null +++ b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/FieldMaskingSpanQuery.java @@ -0,0 +1,155 @@ +package org.apache.lucene.search.spans; + +/** + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 java.io.IOException; +import java.util.Set; + +import org.apache.lucene.index.IndexReader; +import org.apache.lucene.index.Term; +import org.apache.lucene.search.Query; +import org.apache.lucene.search.Weight; +import org.apache.lucene.search.Searcher; +import org.apache.lucene.search.Similarity; +import org.apache.lucene.util.ToStringUtils; + +/** + *
Wrapper to allow {@link SpanQuery} objects participate in composite + * single-field SpanQueries by 'lying' about their search field. That is, + * the masked SpanQuery will function as normal, + * but {@link SpanQuery#getField()} simply hands back the value supplied + * in this class's constructor.
+ * + *This can be used to support Queries like {@link SpanNearQuery} or + * {@link SpanOrQuery} across different fields, which is not ordinarily + * permitted.
+ * + *This can be useful for denormalized relational data: for example, when + * indexing a document with conceptually many 'children':
+ * + *+ * teacherid: 1 + * studentfirstname: james + * studentsurname: jones + * + * teacherid: 2 + * studenfirstname: james + * studentsurname: smith + * studentfirstname: sally + * studentsurname: jones + *+ * + *
a SpanNearQuery with a slop of 0 can be applied across two + * {@link SpanTermQuery} objects as follows: + *
+ * SpanQuery q1 = new SpanTermQuery(new Term("studentfirstname", "james")); + * SpanQuery q2 = new SpanTermQuery(new Term("studentsurname", "jones")); + * SpanQuery q2m = new FieldMaskingSpanQuery(q2, "studentfirstname"); + * Query q = new SpanNearQuery(new SpanQuery[]{q1, q2m}, -1, false); + *+ * to search for 'studentfirstname:james studentsurname:jones' and find + * teacherid 1 without matching teacherid 2 (which has a 'james' in position 0 + * and 'jones' in position 1). + * + *
Note: as {@link #getField()} returns the masked field, scoring will be + * done using the norms of the field name supplied. This may lead to unexpected + * scoring behaviour.
+ */ +public class FieldMaskingSpanQuery extends SpanQuery { + private SpanQuery maskedQuery; + private String field; + + public FieldMaskingSpanQuery(SpanQuery maskedQuery, String maskedField) { + this.maskedQuery = maskedQuery; + this.field = maskedField; + } + + @Override + public String getField() { + return field; + } + + public SpanQuery getMaskedQuery() { + return maskedQuery; + } + + // :NOTE: getBoost and setBoost are not proxied to the maskedQuery + // ...this is done to be more consistent with things like SpanFirstQuery + + @Override + public Spans getSpans(IndexReader reader) throws IOException { + return maskedQuery.getSpans(reader); + } + + @Override + public void extractTerms(Set