Java Operation MongoDB (connection pool)

Original link:Java operation MongoDB (connection pool)

The MONGO instance is actually a database connection pool, which has 10 links in the default connection pool. There is no need to re-implement this link pool, but we can change the configuration of this connection pool. Because the MONGO instance is a connection pool, it is best to have only one instance of MONGO in the project.

Common Configuration parameters:

connectionsperhost: Number of connections per host

threadsallowedtoblockforconnectionmultiplier: The number of thread queues, the result of which is multiplied by the above Connectionsperhost value is the maximum thread queue value. The "out of semaphores to get DB" error is thrown if the connection thread is fully queued.

maxwaittime: The maximum waiting time for a connected thread to block

connecttimeout: The milliseconds that the connection timed out. 0 is the default and unlimited

sockettimeout: The socket timed out. 0 is the default and unlimited

autoconnectretry: If this control is in a connection, the system will automatically retry

There are also many configurations that can be found in the MongoDB API.

Here's a look at the code:

[Java]View PlainCopyprint?

2. Package Com.mongo.common;
6. Import java.net.UnknownHostException;
10. Import Com.mongodb.DB;
12. Import Com.mongodb.Mongo;
14. Import com.mongodb.MongoException;
16. Import com.mongodb.MongoOptions;
20. Public class Mongomanager {
22. Private final static String HOST = "localhost"; Port
24. Private final static int PORT = 27017; Port
26. Private final static int poolsize = + ; Number of connections
28. Private final static int BLOCKSIZE = 100; //wait Queue Length
30. private static Mongo Mongo = null;
34. Private Mongomanager () {}
38. Static {
40. Initdbprompties ();
42. }
46. public static DB Getdb (String dbName) {
48. return Mongo.getdb (dbName);
50. }
54. /** 
56. * Initialize Connection Pool
58. */
60. private static void Initdbprompties () {
62. //Other parameters to be added according to the actual situation
64. try {
66. MONGO = new Mongoclient (HOST, PORT);
68. Mongooptions opt = mongo.getmongooptions ();
70. Opt.connectionsperhost = poolsize;
72. Opt.threadsallowedtoblockforconnectionmultiplier = BLOCKSIZE;
74. } catch (Unknownhostexception e) {
76. } catch (Mongoexception e) {
80. }
84. }
86. }

When used, as follows:

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2. /**
4. * Save
6. *
8. * @param user
10. * @throws unknownhostexception
12. */
14. public void Save (user user) throws unknownhostexception {
16. DB Mymongo = Mongomanager.getdb ("Mymongo");
18. Dbcollection usercollection = mymongo.getcollection ("user");
22. DBObject dbo = (dbobject) json.parse (User.tojson ());
24. Usercollection.insert (dbo);
26. }

Java Operation MongoDB (Connection pool) (RPM)