Thanks Sven for the quick response. I am a beginner to iBatis, so I
apologize in advance if I don't know some of the answers to your questions.
I'll try my best.
In regards to 2), I figured that was the case by the same reasoning. I just
wanted to make sure with someone who had more experience with iBatis.
However, is it possible one iBatis application receive notifications from
another iBatis application to flush cache?
In regards to 1), the full stack trace is below. Thanks for looking at this.
Also, how would I deactivate the ping query?
Exception in thread "main"
org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get
JDBC Connection; nested exception is com.mysql.jdbc.CommunicationsException:
Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: java.net.ConnectException: Connection refused: connect
STACKTRACE:
java.net.SocketException: java.net.ConnectException: Connection refused:
connect
at
com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:156)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2555)
at com.mysql.jdbc.Connection.<init>(Connection.java:1485)
at
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at
org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:37)
at
org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:290)
at
org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:771)
at
org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:95)
at
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540)
at
org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
at
org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:178)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.executeWithListResult(SqlMapClientTemplate.java:204)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.queryForList(SqlMapClientTemplate.java:243)
at data.SqlMapClientTestDao.getAll(SqlMapClientTestDao.java:25)
at service.Main.run(Main.java:37)
at service.Main.main(Main.java:55)
** END NESTED EXCEPTION **
Last packet sent to the server was 0 ms ago.
com.mysql.jdbc.CommunicationsException: Communications link failure due to
underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: java.net.ConnectException: Connection refused: connect
STACKTRACE:
java.net.SocketException: java.net.ConnectException: Connection refused:
connect
at
com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:156)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2555)
at com.mysql.jdbc.Connection.<init>(Connection.java:1485)
at
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at
org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:37)
at
org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:290)
at
org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:771)
at
org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:95)
at
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540)
at
org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
at
org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:178)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.executeWithListResult(SqlMapClientTemplate.java:204)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.queryForList(SqlMapClientTemplate.java:243)
at data.SqlMapClientTestDao.getAll(SqlMapClientTestDao.java:25)
at service.Main.run(Main.java:37)
at service.Main.main(Main.java:55)
** END NESTED EXCEPTION **
Last packet sent to the server was 0 ms ago.
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2621)
at com.mysql.jdbc.Connection.<init>(Connection.java:1485)
at
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at
org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:37)
at
org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:290)
at
org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:771)
at
org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:95)
at
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540)
at
org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
at
org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:178)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.executeWithListResult(SqlMapClientTemplate.java:204)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.queryForList(SqlMapClientTemplate.java:243)
at data.SqlMapClientTestDao.getAll(SqlMapClientTestDao.java:25)
at service.Main.run(Main.java:37)
at service.Main.main(Main.java:55)
----- Original Message -----
From: "Sven Boden" <[EMAIL PROTECTED]>
To: <user-java@ibatis.apache.org>
Sent: Wednesday, April 19, 2006 4:48 PM
Subject: Re: cacheModel - Database Down and external app flush
For 1):
do you have the full nested stacktrace? Did you deactivate the ping query?
and are you sure the exception originates in iBATIS (we'll see from the
full stacktrace). The intention of a cache is to speed things up, it's not
the intention to have a complete in-core database.
For 2)
There's no way for iBATIS to be automatically aware of updates by other
applications. This is a problem for every database application, not just
iBATIS. If you would develop an application without iBATIS (with your own
developed caching), how would you know in your application whether another
application updated your database?
Regards,
Sven
James Johnson wrote:
I have a few questions regarding iBatis cacheModel. All help is greatly
appreciated.
1) When the iBatis cacheModel is used, a connection to the database server
appears to be still required. The data has been cached, so I'm not sure
why the database server needs to be up after caching the data.
For exapmle, I have test code that basically returns the same row of data
n times. As expected, the data is cached and remains unchanged desipte
making updates using the database command line client (i.e. outside of my
program). During the ith (1<i<=n) try, I shutdown the database server. I
would expect iBatis to just use the cache results and not require the
database server to be up. However, instead I get the following error when
I bring the database server down:
Exception in thread "main"
org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get
JDBC Connection; nested exception is
com.mysql.jdbc.CommunicationsException: Communications link failure due to
underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: java.net.ConnectException: Connection refused: connect
I would like to have mechanism that allows the application to use cached
data in the event the database server is down as it does when the database
server is up. Is the cachModel capable of providing this functionality?
Why does the database server need to be up when iBatis is using cached
results?
2) By specifying the flushOnExecute, iBatis will flush the cache when a
certian statement(s) is executed. Is there a way for iBatis to flush the
cache when anything (i.e. another application) makes an update, insert or
delete?
