Remove unsued code in suggester and convert for loops to stream

Signed-off-by: Gino Augustine <[email protected]>

Author: ginoaugustine

suggester/src/main/java/org/opengrok/suggest/query/customized/CustomExactPhraseScorer.java

@@ -17,17 +17,20 @@
 package org.opengrok.suggest.query.customized;
 
 import java.io.IOException;
-import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+import java.util.stream.Collectors;
 
 import org.apache.lucene.index.PostingsEnum;
 import org.apache.lucene.search.ConjunctionUtils;
 import org.apache.lucene.search.DocIdSetIterator;
 import org.apache.lucene.search.Scorer;
 import org.apache.lucene.search.TwoPhaseIterator;
 import org.apache.lucene.search.Weight;
+import org.jetbrains.annotations.NotNull;
 import org.opengrok.suggest.query.PhraseScorer;
 import org.opengrok.suggest.query.data.BitIntsHolder;
 import org.opengrok.suggest.query.data.IntsHolder;
@@ -50,9 +53,9 @@ private static class PostingsAndPosition {
     }
 
     // custom begins – only necessary attributes
-    private Map<Integer, IntsHolder> documentToPositionsMap = new HashMap<>();
+    private final Map<Integer, IntsHolder> documentToPositionsMap = new HashMap<>();
 
-    private int offset;
+    private final int offset;
 
     private final DocIdSetIterator conjunction;
     private final PostingsAndPosition[] postings;
@@ -74,21 +77,22 @@ private static class PostingsAndPosition {
 
         this.offset = offset; // custom
 
-        List<DocIdSetIterator> iterators = new ArrayList<>();
-        List<PostingsAndPosition> postingsAndPositions = new ArrayList<>();
-        for (CustomPhraseQuery.PostingsAndFreq posting : postings) {
-            iterators.add(posting.postings);
-            postingsAndPositions.add(new PostingsAndPosition(posting.postings, posting.position));
-        }
         // custom begins – support for single term
-        if (iterators.size() == 1) {
-            conjunction = iterators.get(0);
-        } else {
-            conjunction = ConjunctionUtils.intersectIterators(iterators);
-        }
+        conjunction = generateDocIdSetIterator(Arrays.stream(postings)
+                .map(p -> p.postings).collect(Collectors.toList()));
         // custom ends
         assert TwoPhaseIterator.unwrap(conjunction) == null;
-        this.postings = postingsAndPositions.toArray(new PostingsAndPosition[postingsAndPositions.size()]);
+        this.postings = Arrays.stream(postings)
+                .map(p -> new PostingsAndPosition(p.postings, p.position))
+                .toArray(PostingsAndPosition[]::new);
+    }
+
+    private DocIdSetIterator generateDocIdSetIterator(@NotNull List<DocIdSetIterator> listOfDocIdSetIterator) {
+        return Optional.of(listOfDocIdSetIterator)
+                .filter(p -> p.size() > 1)
+                .map(ConjunctionUtils::intersectIterators)
+                .orElse(listOfDocIdSetIterator.get(0));
+
     }
 
     @Override

suggester/src/main/java/org/opengrok/suggest/query/customized/CustomPhraseQuery.java

@@ -40,7 +40,7 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Objects;
-import java.util.Set;
+import java.util.stream.IntStream;
 
 /**
  * Modified Apache Lucene's {@link PhraseQuery} to allow to use {@link CustomExactPhraseScorer} and
@@ -93,27 +93,19 @@ public void setOffset(int offset) {
     }
 
     private static int[] incrementalPositions(int length) {
-        int[] positions = new int[length];
-        for (int i = 0; i < length; ++i) {
-            positions[i] = i;
-        }
-        return positions;
+        return IntStream.range(0,length).toArray();
     }
 
     private static Term[] toTerms(String field, String... termStrings) {
-        Term[] terms = new Term[termStrings.length];
-        for (int i = 0; i < terms.length; ++i) {
-            terms[i] = new Term(field, termStrings[i]);
-        }
-        return terms;
+        return Arrays.stream(termStrings)
+                .map(termString -> new Term(field,termString))
+                .toArray(Term[]::new);
     }
 
     private static Term[] toTerms(String field, BytesRef... termBytes) {
-        Term[] terms = new Term[termBytes.length];
-        for (int i = 0; i < terms.length; ++i) {
-            terms[i] = new Term(field, termBytes[i]);
-        }
-        return terms;
+        return Arrays.stream(termBytes)
+                .map(termByte -> new Term(field,termByte))
+                .toArray(Term[]::new);
     }
 
     /**
@@ -251,9 +243,9 @@ public Weight createWeight(IndexSearcher searcher, ScoreMode scoreMode, float bo
 
     private static class CustomPhraseWeight extends Weight {
 
-        private CustomPhraseQuery query;
+        private final CustomPhraseQuery query;
 
-        private TermStates[] states;
+        private final TermStates[] states;
 
         CustomPhraseWeight(IndexSearcher searcher, CustomPhraseQuery query) throws IOException {
             super(query);
@@ -268,11 +260,6 @@ private static class CustomPhraseWeight extends Weight {
             }
         }
 
-        @Deprecated
-        public void extractTerms(Set<Term> set) {
-            throw new UnsupportedOperationException();
-        }
-
         @Override
         public Explanation explain(LeafReaderContext leafReaderContext, int i) {
             throw new UnsupportedOperationException();

suggester/src/main/java/org/opengrok/suggest/query/customized/CustomSloppyPhraseScorer.java

@@ -23,7 +23,10 @@
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+import java.util.stream.Collectors;
 
 import org.apache.lucene.index.Term;
 import org.apache.lucene.search.ConjunctionUtils;
@@ -32,6 +35,7 @@
 import org.apache.lucene.search.TwoPhaseIterator;
 import org.apache.lucene.search.Weight;
 import org.apache.lucene.util.FixedBitSet;
+import org.jetbrains.annotations.NotNull;
 import org.opengrok.suggest.query.PhraseScorer;
 import org.opengrok.suggest.query.data.BitIntsHolder;
 import org.opengrok.suggest.query.data.IntsHolder;
@@ -60,9 +64,9 @@ final class CustomSloppyPhraseScorer extends Scorer implements PhraseScorer { //
     private PhrasePositions[] rptStack; // temporary stack for switching colliding repeating pps
 
     // custom begins
-    private int offset;
+    private final int offset;
 
-    private Map<Integer, IntsHolder> documentsToPositionsMap = new HashMap<>();
+    private final Map<Integer, IntsHolder> documentsToPositionsMap = new HashMap<>();
     // custom ends
 
     // custom – constructor parameters
@@ -84,20 +88,24 @@ final class CustomSloppyPhraseScorer extends Scorer implements PhraseScorer { //
         this.offset = offset; // custom
         this.numPostings = postings.length;
         pq = new PhraseQueue(postings.length);
-        DocIdSetIterator[] iterators = new DocIdSetIterator[postings.length];
         phrasePositions = new PhrasePositions[postings.length];
         for (int i = 0; i < postings.length; ++i) {
-            iterators[i] = postings[i].postings;
             phrasePositions[i] = new PhrasePositions(postings[i].postings, postings[i].position, i, postings[i].terms);
         }
         // custom begins – support for single term
-        if (iterators.length == 1) {
-            conjunction = iterators[0];
-        } else {
-            conjunction = ConjunctionUtils.intersectIterators(Arrays.asList(iterators));
-        }
+        conjunction = generateDocIdSetIterator(Arrays.stream(postings)
+                .map(p -> p.postings).collect(Collectors.toList()));
         // custom ends
         assert TwoPhaseIterator.unwrap(conjunction) == null;
+
+    }
+
+    private DocIdSetIterator generateDocIdSetIterator(@NotNull List<DocIdSetIterator> listOfDocIdSetIterator) {
+        return Optional.of(listOfDocIdSetIterator)
+                .filter(p -> p.size() > 1)
+                .map(ConjunctionUtils::intersectIterators)
+                .orElse(listOfDocIdSetIterator.get(0));
+
     }
 
     /**

suggester/src/main/java/org/opengrok/suggest/query/customized/PhrasePositions.java

@@ -33,7 +33,6 @@ final class PhrasePositions {
     int offset;           // position in phrase
     final int ord;                                  // unique across all PhrasePositions instances
     final PostingsEnum postings;            // stream of docs & positions
-    PhrasePositions next;                           // used to make lists
     int rptGroup = -1; // >=0 indicates that this is a repeating PP
     int rptInd; // index in the rptGroup
     final Term[] terms; // for repetitions initialization