Help! Could not retrieve a database connection

[jamieyg3]

Hey

I made a custom login, and it seems to work 10 times but on the 11th time I get this msg:

Code: Select all

jvm 1    | 23:34:31.413 - [ WARNING ] > Could not retrieve a database connection: org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool exhausted
jvm 1    | org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool exhausted
jvm 1    |      at org.apache.commons.dbcp.PoolingDriver.connect(PoolingDriver.java:183)
jvm 1    |      at java.sql.DriverManager.getConnection(Unknown Source)
jvm 1    |      at java.sql.DriverManager.getConnection(Unknown Source)
jvm 1    |      at it.gotoandplay.smartfoxserver.db.DbManager.getConnection(DbManager.java:218)
jvm 1    |      at sacredseasons.Database.tryLogin(Database.java:28)
jvm 1    |      at sacredseasons.Login.loginRequest(Login.java:93)
jvm 1    |      at sacredseasons.Login.handleInternalEvent(Login.java:75)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.MessageHandler.dispatchEvent(MessageHandler.java:141)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.handleLoginRequest(SystemHandler.java:439)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.processEvent(SystemHandler.java:194)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.run(SystemHandler.java:143)
jvm 1    |      at java.lang.Thread.run(Unknown Source)
jvm 1    | Caused by: java.util.NoSuchElementException
jvm 1    |      at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:744)
jvm 1    |      at org.apache.commons.dbcp.PoolingDriver.connect(PoolingDriver.java:175)
jvm 1    |      ... 11 more
jvm 1    | java.lang.NullPointerException
jvm 1    |      at sacredseasons.Database.tryLogin(Database.java:32)
jvm 1    |      at sacredseasons.Login.loginRequest(Login.java:93)
jvm 1    |      at sacredseasons.Login.handleInternalEvent(Login.java:75)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.MessageHandler.dispatchEvent(MessageHandler.java:141)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.handleLoginRequest(SystemHandler.java:439)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.processEvent(SystemHandler.java:194)
jvm 1    |      at it.gotoandplay.smartfoxserver.controllers.SystemHandler.run(SystemHandler.java:143)
jvm 1    |      at java.lang.Thread.run(Unknown Source)
jvm 1    | 23:34:31.414 - [ WARNING ] > SystemHandler: Invalid login request > java.lang.NullPointerException

now I already did a search on these forums for this and found something interesting, other people who are getting this error are also doing this:

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Connection con=db.getConnection();

which I am also doing, because I wanted to use PreparedStatements to avoid injection attacks. All I have to do to trigger this problem is try to login with the same user with a bad password 11 times.

now... if I don't use db.getConnection() I do not get this problem at all!!! but then I can't use the PreparedStatements...

so I don't mind not using db.getConnection() as long as there is a good way to clean (escape) strings before I put them into an sql statement!

Please advise me what to do!

[shvilam]

do you close the connection ?

[jamieyg3]

do you close the connection ?

thanks for the quick reply.

Yes the connection is being closed.

[Lapo]

You can change the policy of the pool to GROW in order to allow the pool of connection to become larger than the size specified in the config.
Check chapter 6.3 of the docs for all the details

[jamieyg3]

You can change the policy of the pool to GROW in order to allow the pool of connection to become larger than the size specified in the config.
Check chapter 6.3 of the docs for all the details

i saw that but something is not right. it works fine without having to grow as long as i dont use db.getConnection().

[Lapo]

if you use getConnection() then you have to manually close that connection or it won't be returned to the pool