I'm using read committed. My guess has been that this, as you points
out, is the first thing done with the connection and therefore the first
thing to fail.
I have looked once again at the code and there is some things that
puzzles me. There are a lot of connection and transaction factories
involved and I am not sure that all of them are working together. I am
using geronimo transaction factory. I thought that the best place to
catch the SQLException was in ConnectionFactory, but then I discovered
that the SQLException was eaten on its way up to that class. An
SQLException is thrown by the Connector package, but it is catched by
the XAConnectionFactory and there it is rethrown as a RuntimeException
(why??).
I have tried to handle this error in XAConnectionFactory and ObjectPool,
like this:
In XAConnectionFactory in the prepareObject-method I changed to this:
try {
((XAConnectionImpl)
con).setTransactionIsolation(transactionIsolation);
} catch (SQLException sex) {
String sqlState = sex.getSQLState();
if ("08S01".equals(sqlState) ||
"40001".equals(sqlState)) {
return null;
}
else {
throw new RuntimeException("Unable to
setTransactionIsolation: " + sex.getMessage());
}
}
In ObjectPool I added this code after the prepareObject-statement:
result = factory.prepareObject(ob);
if (result == null) {
markObjectAsInvalid(ob);
releaseObject(ob);
try {
rec = createNewObject(parameters);
ob = rec.getObject();
} catch (Exception e) {
log.error("Exception in creating new object for
pool", e);
permits.release();
throw e;
}
result = factory.prepareObject(ob);
if (result == null) {
throw new RuntimeException("Unable to
setTransactionIsolation");
}
}
This doesn't work because a new Connection is not created. Perhaps it is
impossible to create a new connection inside the object-pool? But where
can this be handled?
Any suggestions?
/ Hans
David E Jones skrev:
This is an interesting stack trace because the problem is happening
when it tries to set the transaction isolation level...
Which isolation level do you have configured? This may not be the
problem since this is one of the first things that happens when a new
connection is created or when an existing connection is re-used. This
might be good to look into though.
-David
On Oct 23, 2006, at 4:41 PM, Hans Holmlund wrote:
The Newer versions of the MySQL connector doesn't support
autoReconnect anymore (however there is a property
enableDeprecatedAutoreconnect, default is false, which can change
that). The reason for deprecating this feature might be valid (and I
don't have any opinion on that) but it will cause a lot of problem.
Unfortunately so does MySQLs suggested method not work properly
either. This might be something with how the pooling is done in
EntityEngine. When a connection is disconnected by the DB (i.e. after
wait_timeout seconds, a MySQL property that can be changed) a
SQLException should be thrown if that connection is used again. But
what I get is the following;
java.io.EOFException
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1913)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2304)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2803)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1573)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1665)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3118)
at
com.mysql.jdbc.Connection.setTransactionIsolation(Connection.java:5499)
at
org.ofbiz.minerva.pool.jdbc.xa.wrapper.XAConnectionImpl.setTransactionIsolation(XAConnectionImpl.java:117)
at
org.ofbiz.minerva.pool.jdbc.xa.XAConnectionFactory.prepareObject(XAConnectionFactory.java:412)
at
org.ofbiz.minerva.pool.ObjectPool.getObject(ObjectPool.java:645)
at
org.ofbiz.minerva.pool.jdbc.xa.XAPoolDataSource.getConnection(XAPoolDataSource.java:355)
at
org.ofbiz.entity.transaction.MinervaConnectionFactory.getConnection(MinervaConnectionFactory.java:56)
at
org.ofbiz.geronimo.GeronimoTransactionFactory.getConnection(GeronimoTransactionFactory.java:94)
at
org.ofbiz.entity.transaction.TransactionFactory.getConnection(TransactionFactory.java:104)
at
org.ofbiz.entity.jdbc.ConnectionFactory.getConnection(ConnectionFactory.java:86)
I suppose ConnectionFactory might be a good place to catch the
exceptions, but I am not sure about what to do with the EOFException.
Does anyone has any ideas?
"why not just schedule a simple service that will hit the database
every hour or so." This is not a good idea, unless it is done from
inside the pool.
/ Hans Holmlund
Si Chen skrev:
The OFBiz JDBC url already has autoReconnect=true.
That was my first contribution ever to ofbiz!
On Oct 21, 2006, at 6:38 AM, Hans Holmlund wrote:
I have a problem with MySQL connections who fails. I get a
com.mysql.jdbc.exceptions.MySQLNonTransientConnectionException. I
found an explanation for this in an help page from MySQL
(http://dev.mysql.com/doc/refman/5.0/en/connector-j-usagenotes-troubleshooting.html#qandaitem-24-3-5-3-4):
" MySQL closes connections after 8 hours of inactivity. You either
need to use a connection pool that handles stale connections or use
the "autoReconnect" parameter. /-/ *Note. * Use of the
|autoReconnect| option is not recommended because there is no safe
method of reconnecting to the MySQL server without risking some
corruption of the connection state or database state information.
Instead, you should use a connection pool which will enable your
application to connect to the MySQL server using an available
connection from the pool. The |autoReconnect| facility is
deprecated, and may be removed in a future release."
This (managing stale connection) is not how EntityEngine has done
its implementation, with EE you can only set autoReconnect to true.
I wonder if you have planned to change this. In the above mentioned
page there is some example code, so this should be an easy thing to
fix.
Thanks,
Hans Holmlund
org.ofbiz.geronimo.GeronimoTransactionFactory - Geronimo is the
configured transaction manager but there was an error getting a
database Connection through Geronimo for the mysql datasource.
Please check your configuration, class path, etc.
java.lang.RuntimeException: Unable to setTransactionIsolation:
Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.io.EOFException
STACKTRACE:
java.io.EOFException
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1913)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2304)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2803)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1573)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1665)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3118)
at
com.mysql.jdbc.Connection.setTransactionIsolation(Connection.java:5499)
at
org.ofbiz.minerva.pool.jdbc.xa.wrapper.XAConnectionImpl.setTransactionIsolation(XAConnectionImpl.java:117)
at
org.ofbiz.minerva.pool.jdbc.xa.XAConnectionFactory.prepareObject(XAConnectionFactory.java:412)
at
org.ofbiz.minerva.pool.ObjectPool.getObject(ObjectPool.java:645)
at
org.ofbiz.minerva.pool.jdbc.xa.XAPoolDataSource.getConnection(XAPoolDataSource.java:355)
at
org.ofbiz.entity.transaction.MinervaConnectionFactory.getConnection(MinervaConnectionFactory.java:56)
at
org.ofbiz.geronimo.GeronimoTransactionFactory.getConnection(GeronimoTransactionFactory.java:94)
at
org.ofbiz.entity.transaction.TransactionFactory.getConnection(TransactionFactory.java:104)
at
org.ofbiz.entity.jdbc.ConnectionFactory.getConnection(ConnectionFactory.java:82)
at
org.ofbiz.entity.jdbc.SQLProcessor.getConnection(SQLProcessor.java:268)
at
org.ofbiz.entity.jdbc.SQLProcessor.prepareStatement(SQLProcessor.java:374)
at
org.ofbiz.entity.jdbc.SQLProcessor.prepareStatement(SQLProcessor.java:358)
at
org.ofbiz.entity.datasource.GenericDAO.select(GenericDAO.java:539)
at
org.ofbiz.entity.datasource.GenericDAO.select(GenericDAO.java:510)
at
org.ofbiz.entity.datasource.GenericHelperDAO.findByPrimaryKey(GenericHelperDAO.java:90)
at
org.ofbiz.entity.GenericDelegator.findByPrimaryKey(GenericDelegator.java:1248)
at
org.ofbiz.entity.GenericDelegator.findByPrimaryKey(GenericDelegator.java:1304)
Best Regards,
Si
[EMAIL PROTECTED]
