summaryrefslogtreecommitdiff
path: root/core/src/main/java/org/elasticsearch/index/fielddata/fieldcomparator/BytesRefFieldComparatorSource.java
blob: c433836417a0ffe056207d27abe0d4f0ba67b3dd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.
 */

package org.elasticsearch.index.fielddata.fieldcomparator;

import org.apache.lucene.index.BinaryDocValues;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.index.SortedSetDocValues;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.FieldComparator;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.SortField;
import org.apache.lucene.util.BitSet;
import org.apache.lucene.util.BytesRef;
import org.elasticsearch.index.fielddata.AbstractSortedDocValues;
import org.elasticsearch.index.fielddata.IndexFieldData;
import org.elasticsearch.index.fielddata.IndexOrdinalsFieldData;
import org.elasticsearch.index.fielddata.SortedBinaryDocValues;
import org.elasticsearch.search.MultiValueMode;

import java.io.IOException;

/**
 * Comparator source for string/binary values.
 */
public class BytesRefFieldComparatorSource extends IndexFieldData.XFieldComparatorSource {

    private final IndexFieldData<?> indexFieldData;
    private final MultiValueMode sortMode;
    private final Object missingValue;
    private final Nested nested;

    public BytesRefFieldComparatorSource(IndexFieldData<?> indexFieldData, Object missingValue, MultiValueMode sortMode, Nested nested) {
        this.indexFieldData = indexFieldData;
        this.sortMode = sortMode;
        this.missingValue = missingValue;
        this.nested = nested;
    }

    @Override
    public SortField.Type reducedType() {
        return SortField.Type.STRING;
    }

    @Override
    public Object missingValue(boolean reversed) {
        if (sortMissingFirst(missingValue) || sortMissingLast(missingValue)) {
            if (sortMissingLast(missingValue) ^ reversed) {
                return SortField.STRING_LAST;
            } else {
                return SortField.STRING_FIRST;
            }
        }
        // otherwise we fill missing values ourselves
        return null;
    }

    protected SortedBinaryDocValues getValues(LeafReaderContext context) throws IOException {
        return indexFieldData.load(context).getBytesValues();
    }

    protected void setScorer(Scorer scorer) {}

    @Override
    public FieldComparator<?> newComparator(String fieldname, int numHits, int sortPos, boolean reversed) {
        assert indexFieldData == null || fieldname.equals(indexFieldData.getFieldName());

        final boolean sortMissingLast = sortMissingLast(missingValue) ^ reversed;
        final BytesRef missingBytes = (BytesRef) missingObject(missingValue, reversed);
        if (indexFieldData instanceof IndexOrdinalsFieldData) {
            return new FieldComparator.TermOrdValComparator(numHits, null, sortMissingLast) {

                @Override
                protected SortedDocValues getSortedDocValues(LeafReaderContext context, String field) throws IOException {
                    final SortedSetDocValues values = ((IndexOrdinalsFieldData) indexFieldData).load(context).getOrdinalsValues();
                    final SortedDocValues selectedValues;
                    if (nested == null) {
                        selectedValues = sortMode.select(values);
                    } else {
                        final BitSet rootDocs = nested.rootDocs(context);
                        final DocIdSetIterator innerDocs = nested.innerDocs(context);
                        selectedValues = sortMode.select(values, rootDocs, innerDocs);
                    }
                    if (sortMissingFirst(missingValue) || sortMissingLast(missingValue)) {
                        return selectedValues;
                    } else {
                        return new ReplaceMissing(selectedValues, missingBytes);
                    }
                }

                @Override
                public void setScorer(Scorer scorer) {
                    BytesRefFieldComparatorSource.this.setScorer(scorer);
                }

            };
        }

        return new FieldComparator.TermValComparator(numHits, null, sortMissingLast) {

            @Override
            protected BinaryDocValues getBinaryDocValues(LeafReaderContext context, String field) throws IOException {
                final SortedBinaryDocValues values = getValues(context);
                final BinaryDocValues selectedValues;
                if (nested == null) {
                    selectedValues = sortMode.select(values, missingBytes);
                } else {
                    final BitSet rootDocs = nested.rootDocs(context);
                    final DocIdSetIterator innerDocs = nested.innerDocs(context);
                    selectedValues = sortMode.select(values, missingBytes, rootDocs, innerDocs, context.reader().maxDoc());
                }
                return selectedValues;
            }

            @Override
            public void setScorer(Scorer scorer) {
                BytesRefFieldComparatorSource.this.setScorer(scorer);
            }

        };
    }

    /**
     * A view of a SortedDocValues where missing values
     * are replaced with the specified term
     */
    // TODO: move this out if we need it for other reasons
    static class ReplaceMissing extends AbstractSortedDocValues {
        final SortedDocValues in;
        final int substituteOrd;
        final BytesRef substituteTerm;
        final boolean exists;
        boolean hasValue;

        ReplaceMissing(SortedDocValues in, BytesRef term) throws IOException {
            this.in = in;
            this.substituteTerm = term;
            int sub = in.lookupTerm(term);
            if (sub < 0) {
                substituteOrd = -sub-1;
                exists = false;
            } else {
                substituteOrd = sub;
                exists = true;
            }
        }

        @Override
        public int ordValue() throws IOException {
            if (hasValue == false) {
                return substituteOrd;
            }
            int ord = in.ordValue();
            if (exists == false && ord >= substituteOrd) {
                return ord + 1;
            } else {
                return ord;
            }
        }

        @Override
        public boolean advanceExact(int target) throws IOException {
            hasValue = in.advanceExact(target);
            return true;
        }

        @Override
        public int docID() {
            return in.docID();
        }

        @Override
        public int getValueCount() {
            if (exists) {
                return in.getValueCount();
            } else {
                return in.getValueCount() + 1;
            }
        }

        @Override
        public BytesRef lookupOrd(int ord) throws IOException {
            if (ord == substituteOrd) {
                return substituteTerm;
            } else if (exists == false && ord > substituteOrd) {
                return in.lookupOrd(ord-1);
            } else {
                return in.lookupOrd(ord);
            }
        }

        // we let termsenum etc fall back to the default implementation
    }
}