Query DSL: match_phrase_prefix to take boost into account

The match_phrase_prefix query properly parses the boost etc. but it loses it in its rewrite method. Fixed that by setting the orginal boost to the rewritten query before returning it. Also cleaned up some warning in MultiPhrasePrefixQuery.

Closes #13129
Closes #13142

core/src/main/java/org/elasticsearch/common/lucene/search/MultiPhrasePrefixQuery.java

@@ -20,12 +20,7 @@
 package org.elasticsearch.common.lucene.search;
 
 import com.carrotsearch.hppc.ObjectHashSet;
-
+import org.apache.lucene.index.*;
-import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.index.LeafReaderContext;
-import org.apache.lucene.index.Term;
-import org.apache.lucene.index.Terms;
-import org.apache.lucene.index.TermsEnum;
 import org.apache.lucene.search.MatchNoDocsQuery;
 import org.apache.lucene.search.MultiPhraseQuery;
 import org.apache.lucene.search.Query;
@@ -34,12 +29,7 @@ import org.apache.lucene.util.StringHelper;
 import org.apache.lucene.util.ToStringUtils;
 
 import java.io.IOException;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.List;
-import java.util.ListIterator;
 
 public class MultiPhrasePrefixQuery extends Query {
 
@@ -90,7 +80,7 @@ public class MultiPhrasePrefixQuery extends Query {
     public void add(Term[] terms) {
         int position = 0;
         if (positions.size() > 0)
-            position = positions.get(positions.size() - 1).intValue() + 1;
+            position = positions.get(positions.size() - 1) + 1;
 
         add(terms, position);
     }
@@ -98,8 +88,8 @@ public class MultiPhrasePrefixQuery extends Query {
     /**
      * Allows to specify the relative position of terms within the phrase.
      *
-     * @param terms
+     * @param terms the terms
-     * @param position
+     * @param position the position of the terms provided as argument
      * @see org.apache.lucene.search.PhraseQuery#add(Term, int)
      */
     public void add(Term[] terms, int position) {
@@ -115,15 +105,7 @@ public class MultiPhrasePrefixQuery extends Query {
         }
 
         termArrays.add(terms);
-        positions.add(Integer.valueOf(position));
+        positions.add(position);
-    }
-
-    /**
-     * Returns a List of the terms in the multiphrase.
-     * Do not modify the List or its contents.
-     */
-    public List<Term[]> getTermArrays() {
-        return Collections.unmodifiableList(termArrays);
     }
 
     /**
@@ -132,7 +114,7 @@ public class MultiPhrasePrefixQuery extends Query {
     public int[] getPositions() {
         int[] result = new int[positions.size()];
         for (int i = 0; i < positions.size(); i++)
-            result[i] = positions.get(i).intValue();
+            result[i] = positions.get(i);
         return result;
     }
 
@@ -160,6 +142,7 @@ public class MultiPhrasePrefixQuery extends Query {
             return Queries.newMatchNoDocsQuery();
         }
         query.add(terms.toArray(Term.class), position);
+        query.setBoost(getBoost());
         return query.rewrite(reader);
     }
 

core/src/test/java/org/elasticsearch/common/lucene/search/MultiPhrasePrefixQueryTests.java

@@ -23,13 +23,12 @@ import org.apache.lucene.document.Document;
 import org.apache.lucene.document.Field;
 import org.apache.lucene.document.TextField;
 import org.apache.lucene.index.*;
-import org.apache.lucene.search.IndexSearcher;
+import org.apache.lucene.search.*;
 import org.apache.lucene.store.RAMDirectory;
 import org.elasticsearch.common.lucene.Lucene;
 import org.elasticsearch.test.ESTestCase;
 import org.junit.Test;
 
-import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 
 public class MultiPhrasePrefixQueryTests extends ESTestCase {
@@ -63,4 +62,21 @@ public class MultiPhrasePrefixQueryTests extends ESTestCase {
         query.add(new Term("field", "xxx"));
         assertThat(Lucene.count(searcher, query), equalTo(0l));
     }
+
+    @Test
+    public void testBoost() throws Exception {
+        IndexWriter writer = new IndexWriter(new RAMDirectory(), new IndexWriterConfig(Lucene.STANDARD_ANALYZER));
+        Document doc = new Document();
+        doc.add(new Field("field", "aaa bbb", TextField.TYPE_NOT_STORED));
+        writer.addDocument(doc);
+        doc = new Document();
+        doc.add(new Field("field", "ccc ddd", TextField.TYPE_NOT_STORED));
+        writer.addDocument(doc);
+        IndexReader reader = DirectoryReader.open(writer, true);
+        MultiPhrasePrefixQuery multiPhrasePrefixQuery = new MultiPhrasePrefixQuery();
+        multiPhrasePrefixQuery.add(new Term[]{new Term("field", "aaa"), new Term("field", "bb")});
+        multiPhrasePrefixQuery.setBoost(randomFloat());
+        Query query = multiPhrasePrefixQuery.rewrite(reader);
+        assertThat(query.getBoost(), equalTo(multiPhrasePrefixQuery.getBoost()));
+    }
 }