/
Fields.java
73 lines (61 loc) · 1.83 KB
/
Fields.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
package backtype.storm.tuple;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.io.Serializable;
public class Fields implements Iterable<String>, Serializable {
private List<String> _fields;
private Map<String, Integer> _index = new HashMap<String, Integer>();
public Fields(String... fields) {
this(Arrays.asList(fields));
}
public Fields(List<String> fields) {
_fields = new ArrayList<String>(fields.size());
for (String field : fields) {
if (_fields.contains(field))
throw new IllegalArgumentException(
String.format("duplicate field '%s'", field)
);
_fields.add(field);
}
index();
}
public List<Object> select(Fields selector, List<Object> tuple) {
List<Object> ret = new ArrayList<Object>(selector.size());
for(String s: selector) {
ret.add(tuple.get(_index.get(s)));
}
return ret;
}
public List<String> toList() {
return new ArrayList<String>(_fields);
}
public int size() {
return _fields.size();
}
public String get(int index) {
return _fields.get(index);
}
public Iterator<String> iterator() {
return _fields.iterator();
}
public int fieldIndex(String field) {
Integer ret = _index.get(field);
if(ret==null) {
throw new IllegalArgumentException(field + " does not exist");
}
return ret;
}
private void index() {
for(int i=0; i<_fields.size(); i++) {
_index.put(_fields.get(i), i);
}
}
@Override
public String toString() {
return _fields.toString();
}
}