Hi, i want to use c3po with hibernate. Here is my configuration:

<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/ibn</property>
<property name="hibernate.connection.username">xxx</property>
<property name="hibernate.connection.password">xxx</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.isolation">1</property>
<property name="hibernate.jdbc.batch_size">0</property>
<property name="hibernate.order_updates">true</property>
<property name="hibernate.show_sql">false</property>
<property name="hibernate.transaction.factory_class">
org.hibernate.transaction.JDBCTransactionFactory
</property>
<property name="hibernate.c3p0.initialPoolSize">10</property>
<property name="hibernate.c3p0.min_size">10</property>
<property name="hibernate.c3p0.max_size">150</property>
<property name="hibernate.c3p0.timeout">5000</property>
<property name="hibernate.c3p0.max_statements">300</property>
<property name="hibernate.c3po.idle_test_period">3000</property>
<property name="hibernate.c3po.maxIdleTime">30</property>
<property name="hibernate.c3po.propertyCycle">300</property>
<property name="hibernate.c3po.acquireIncrement">3</property>
<property name="hibernate.c3po.testConnectionOnCheckout">false</property>
<property name="hibernate.c3po.autoCommitOnClose">false</property>
<property name="hibernate.c3po.numHelperThreads">10</property>

<property name="hibernate.connection.useCompression">true</property>
<property name="hibernate.connection.cacheResultSetMetadata">true</property>
<property name="hibernate.connection.dontTrackOpenResources">true</property>
<property name="hibernate.connection.dynamicCalendars">true</property>
<property name="hibernate.connection.zeroDateTimeBehavior">convertToNull</property>
<property name="hibernate.connection.rollbackOnPooledClose">true</property>
<property name="hibernate.query.factory_class">org.hibernate.hql.classic.ClassicQueryTranslatorFactory</property>
</session-factory>
</hibernate-configuration>

In another forum i was told, that with this c3po is never used but the hibernate connection-pool. What do i have to change to use c3po??

Any help would be much appreciated.

Thanks
Christoph

hibernate.properties

resp.

hibernate.cfg.xml


By the way, if you're not sure, whether c3p0 is used or not, have a look at your logfile. It tells you which connection pool is used.

Best regards
Sven

Wrong, setting any c3p0.* property is enough to enable the right connection provider. Use your log.

Thanks for your answer. My logfile tells me the following:

Initializing c3p0 pool... com.mchange.v2.c3p0.PoolBackedDataSource@1def3f5 [ connectionPoolDataSource -> com.mchange.v2.c3p0.WrapperConnectionPoolDataSource@165cebb [ acquireIncrement -> 1, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, idleConnectionTestPeriod -> 0, initialPoolSize -> 10, maxIdleTime -> 5000, maxPoolSize -> 150, maxStatements -> 300, maxStatementsPerConnection -> 0, minPoolSize -> 10, nestedDataSource -> com.mchange.v2.c3p0.DriverManagerDataSource@1204425 [ description -> null, driverClass -> null, factoryClassLocation -> null, jdbcUrl -> jdbc:mysql://localhost:3306/ibn, properties -> {dontTrackOpenResources=true, cacheResultSetMetadata=true, user=******, password=******, rollbackOnPooledClose=true, dynamicCalendars=true, zeroDateTimeBehavior=convertToNull, useCompression=true} ] , preferredTestQuery -> null, propertyCycle -> 300, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, usesTraditionalReflectiveProxies -> false ] , factoryClassLocation -> null, numHelperThreads -> 3, poolOwnerIdentityToken -> 1def3f5 ]

So i assume that c3po is running. BUT the properties that i set in the hibernate-configuration (for example maxIdleTime=30) are not set properly. What´s going on here?

Christoph

Because they have the wrong names.

That is all that is supported:

Sorry, i can´t see what´s wrong with the names. Its "maxIdleTime" in the log and "maxIdleTime" in my configuration. Is there any difference that i don´t see?

Christoph

The names in hibernate.properties/hibernate.cfg.xml have underscores, and are not camelCase.

Ok, now i have changed my configuration to the following

<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/ibn</property>
<property name="hibernate.connection.username">ibn</property>
<property name="hibernate.connection.password">gebit</property>
<property name="hibernate.connection.isolation">1</property>
<property name="hibernate.jdbc.batch_size">0</property>
<property name="hibernate.order_updates">true</property>
<property name="hibernate.show_sql">false</property>
<property name="hibernate.transaction.factory_class">
org.hibernate.transaction.JDBCTransactionFactory
</property>
<property name="hibernate.c3p0.initial_pool_size">10</property>
<property name="hibernate.c3p0.min_pool_size">10</property>
<property name="hibernate.c3p0.max_pool_size">150</property>
<property name="hibernate.c3p0.max_statements">300</property>
<property name="hibernate.c3po.idle_connection_test_period">3000</property>
<property name="hibernate.c3po.max_idle_time">30</property>
<property name="hibernate.c3po.acquire_increment">3</property>

<property name="hibernate.connection.use_compression">true</property>
<property name="hibernate.connection.cache_result_set_metadata">true</property>
<property name="hibernate.connection.dont_track_open_resources">true</property>
<property name="hibernate.connection.dynamic_calendars">true</property>
<property name="hibernate.connection.zero_date_time_behavior">convertToNull</property>
<property name="hibernate.connection.rollback_on_pooled_close">true</property>

<property name="hibernate.query.factory_class">org.hibernate.hql.classic.ClassicQueryTranslatorFactory</property>

<!-- Mappings -->
.....
</session-factory>
</hibernate-configuration>

The result is that i don´t get any message in the log about initilizing c3po anymore. What have i done wrong?

Thanks for your help!!!
Christoph

Dude, just use the hibernate.properties file that came with Hibernate3 in the etc/ directory.

cheers mate, now my c3po pool is starting with the properties i want it to have.

Why the limitation? Why H does not use reflection to allow setting all the desired parameters of the pool?
It seems trivial to treat hibernate.c3p0 as a prefix, get all the parameters with the prefix, and then use BeanUtils to set properties on the target object...

BeanUtils? As long as you can write a new connection provider that supports what you want to do without additional dependencies, you are welcome to submit it to JIRA. Of course it can also not break legacy configuration settings.

Adding this code does not break current configuration and allows setting everything else based on reflection (conversion to necessary data type happens automatically too - just tested it):


import org.apache.commons.beanutils.BeanUtils;
....
PoolConfig pcfg = new PoolConfig();
pcfg.setInitialPoolSize(minPoolSize);
pcfg.setMinPoolSize(minPoolSize);
pcfg.setMaxPoolSize(maxPoolSize);
pcfg.setAcquireIncrement(acquireIncrement);
pcfg.setMaxIdleTime(maxIdleTime);
pcfg.setMaxStatements(maxStatements);
pcfg.setIdleConnectionTestPeriod(idleTestPeriod);

//reflection based settings
Enumeration en = props.keys();
String pfx = "hibernate.c3p0.";
while( en.hasMoreElements() ){
String key = (String) en.nextElement();
if( key.startsWith( pfx )){
String setter = key.substring( pfx.length() );
BeanUtils.setProperty( pcfg, setter, props.getProperty( key ) );
}
}



And by the way:
it is necessary to set
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>

in order to enable c3p0 pool

No, it is not necessary (I've documented exactly this for the nth time yesterday for HiA second edition). Please submit patches to JIRA.