forked from senseidb/sensei
/
HashSetDistinctCountMapReduce.java
78 lines (63 loc) · 2.11 KB
/
HashSetDistinctCountMapReduce.java
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
package com.senseidb.search.req.mapred.functions;
import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import org.json.JSONException;
import org.json.JSONObject;
import com.senseidb.search.req.mapred.CombinerStage;
import com.senseidb.search.req.mapred.FacetCountAccessor;
import com.senseidb.search.req.mapred.FieldAccessor;
import com.senseidb.search.req.mapred.IntArray;
import com.senseidb.search.req.mapred.SenseiMapReduce;
import com.senseidb.util.JSONUtil.FastJSONArray;
import com.senseidb.util.JSONUtil.FastJSONObject;
public class HashSetDistinctCountMapReduce implements SenseiMapReduce<HashSet, Integer> {
private String column;
@Override
public void init(JSONObject params) {
column = params.optString("column");
if (column == null) {
throw new IllegalStateException("Column parameter shouldn't be null");
}
}
@Override
public HashSet map(IntArray docId, int docIdCount, long[] uids, FieldAccessor accessor, FacetCountAccessor facetCountAccessor) {
HashSet hashSet = new HashSet(docIdCount);
for (int i =0; i < docIdCount; i++) {
hashSet.add(accessor.getLong(column, docId.get(i)));
}
return hashSet;
}
@Override
public List<HashSet> combine(List<HashSet> mapResults, CombinerStage combinerStage) {
if (mapResults.isEmpty()) {
return mapResults;
}
HashSet ret = mapResults.get(0);
for (int i = 1; i < mapResults.size(); i++) {
ret.addAll(mapResults.get(i));
}
return Arrays.asList(ret);
}
@Override
public Integer reduce(List<HashSet> combineResults) {
if (combineResults.isEmpty()) {
return 0;
}
HashSet ret = combineResults.get(0);
for (int i = 1; i < combineResults.size(); i++) {
ret.addAll(combineResults.get(i));
}
return ret.size();
}
@Override
public JSONObject render(Integer reduceResult) {
// TODO Auto-generated method stub
try {
return new FastJSONObject().put("distinctCount", reduceResult);
} catch (JSONException ex) {
throw new RuntimeException(ex);
}
}
}