This repository has been archived by the owner on Jan 29, 2022. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 603
/
MongoRecordReader.java
112 lines (92 loc) · 2.77 KB
/
MongoRecordReader.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
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
// MongoRecordReader.java
/*
* Copyright 2010 10gen Inc.
*
* Licensed 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 com.mongodb.hadoop.mapred.input;
import com.mongodb.*;
import com.mongodb.hadoop.io.*;
import org.apache.commons.logging.*;
import org.apache.hadoop.mapred.*;
import org.bson.*;
@SuppressWarnings( "deprecation" )
public class MongoRecordReader implements RecordReader<BSONWritable, BSONWritable> {
public MongoRecordReader( MongoInputSplit split ){
_cursor = split.getCursor();
}
public void close(){
if ( _cursor != null )
_cursor.close();
}
public BSONWritable createKey(){
return new BSONWritable();
}
public BSONWritable createValue(){
return new BSONWritable();
}
public BSONObject getCurrentKey(){
return new BasicDBObject( "_id", _current.get( "_id" ) );
}
public BSONObject getCurrentValue(){
return _current;
}
public float getProgress(){
try {
if ( _cursor.hasNext() ){
return 0.0f;
}
else{
return 1.0f;
}
}
catch ( MongoException e ) {
return 1.0f;
}
}
public long getPos(){
return 0; // no progress to be reported, just working on it
}
public void initialize( InputSplit split, TaskAttemptContext context ){
_total = 1.0f;
}
public boolean nextKeyValue(){
try {
if ( !_cursor.hasNext() )
return false;
_current = _cursor.next();
_seen++;
return true;
}
catch ( MongoException e ) {
return false;
}
}
public boolean next( BSONWritable key, BSONWritable value ){
if ( nextKeyValue() ){
log.debug( "Had another k/v" );
key.put( "_id", getCurrentKey().get( "_id" ) );
value.putAll( getCurrentValue() );
return true;
}
else{
log.info( "Cursor exhausted." );
return false;
}
}
private final DBCursor _cursor;
private BSONObject _current;
private float _seen = 0;
private float _total;
private static final Log log = LogFactory.getLog( MongoRecordReader.class );
}