|
1
|
package edu.ucsb.nceas.metacat.dataone;
|
|
2
|
|
|
3
|
import org.apache.log4j.Logger;
|
|
4
|
import org.dataone.cn.index.messaging.IndexTaskMessagingClient;
|
|
5
|
import org.dataone.cn.index.messaging.IndexTaskMessagingClientFactory;
|
|
6
|
|
|
7
|
/**
|
|
8
|
* This class will guarantee to get a single IndexTaskMesagingClient by the singleton pattern
|
|
9
|
* @author tao
|
|
10
|
*
|
|
11
|
*/
|
|
12
|
public class IndexTaskMessagingClientManager {
|
|
13
|
|
|
14
|
private IndexTaskMessagingClient indexTaskClient = null;
|
|
15
|
private static IndexTaskMessagingClientManager manager = null;
|
|
16
|
private static Logger logMetacat = Logger.getLogger(IndexTaskMessagingClientManager.class);
|
|
17
|
|
|
18
|
/**
|
|
19
|
* A thread safe method to get the instance of the manager
|
|
20
|
* @return
|
|
21
|
* @throws InstantiationException
|
|
22
|
* @throws IllegalAccessException
|
|
23
|
* @throws ClassNotFoundException
|
|
24
|
*/
|
|
25
|
public static IndexTaskMessagingClientManager getInstance() throws InstantiationException, IllegalAccessException, ClassNotFoundException {
|
|
26
|
if(manager == null) {
|
|
27
|
synchronized (IndexTaskMessagingClientManager.class) {
|
|
28
|
if(manager == null) {
|
|
29
|
manager = new IndexTaskMessagingClientManager();
|
|
30
|
}
|
|
31
|
}
|
|
32
|
}
|
|
33
|
return manager;
|
|
34
|
}
|
|
35
|
|
|
36
|
/**
|
|
37
|
* Default private constructor
|
|
38
|
* @throws InstantiationException
|
|
39
|
* @throws IllegalAccessException
|
|
40
|
* @throws ClassNotFoundException
|
|
41
|
*/
|
|
42
|
private IndexTaskMessagingClientManager() throws InstantiationException, IllegalAccessException, ClassNotFoundException {
|
|
43
|
initIndexTaskClient();
|
|
44
|
}
|
|
45
|
|
|
46
|
/*
|
|
47
|
* Method to get the index tasks client.
|
|
48
|
*/
|
|
49
|
private void initIndexTaskClient() throws InstantiationException, IllegalAccessException, ClassNotFoundException {
|
|
50
|
if(indexTaskClient == null) {
|
|
51
|
indexTaskClient = IndexTaskMessagingClientFactory.getClient();
|
|
52
|
logMetacat.info("IndexTaskMessagingClientManager.initIndexTaskClient - after generating the client .......................");
|
|
53
|
}
|
|
54
|
}
|
|
55
|
|
|
56
|
/**
|
|
57
|
* Get the client object which can submit the index tasks.
|
|
58
|
* @return
|
|
59
|
*/
|
|
60
|
public IndexTaskMessagingClient getMessagingClient() {
|
|
61
|
return indexTaskClient;
|
|
62
|
}
|
|
63
|
}
|