Java Doc for JdoTransactionManager.java in  » J2EE » spring-framework-2.5 » org » springframework » orm » jdo » Java Source Code / Java DocumentationJava Source Code and Java Documentation

This transaction manager is appropriate for applications that use a single JDO PersistenceManagerFactory for transactional data access. JTA (usually through org.springframework.transaction.jta.JtaTransactionManager ) is necessary for accessing multiple transactional resources within the same transaction. Note that you need to configure your JDO provider accordingly in order to make it participate in JTA transactions.

This transaction manager also supports direct DataSource access within a transaction (i.e. plain JDBC code working with the same DataSource). This allows for mixing services which access JDO and services which use plain JDBC (without being aware of JDO)! Application code needs to stick to the same simple Connection lookup pattern as with org.springframework.jdbc.datasource.DataSourceTransactionManager (i.e. org.springframework.jdbc.datasource.DataSourceUtils.getConnection or going through a org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy ).

Note: To be able to register a DataSource's Connection for plain JDBC code, this instance needs to be aware of the DataSource ( JdoTransactionManager.setDataSource ). The given DataSource should obviously match the one used by the given PersistenceManagerFactory. This transaction manager will autodetect the DataSource that acts as "connectionFactory" of the PersistenceManagerFactory, so you usually don't need to explicitly specify the "dataSource" property.

On JDBC 3.0, this transaction manager supports nested transactions via JDBC 3.0 Savepoints. The JdoTransactionManager.setNestedTransactionAllowed "nestedTransactionAllowed"} flag defaults to "false", though, as nested transactions will just apply to the JDBC Connection, not to the JDO PersistenceManager and its cached objects. You can manually set the flag to "true" if you want to use nested transactions for JDBC access code which participates in JDO transactions (provided that your JDBC driver supports Savepoints). Note that JDO itself does not support nested transactions! Hence, do not expect JDO access code to semantically participate in a nested transaction.
author:
   Juergen Hoeller
since:
   03.06.2003
See Also:   JdoTransactionManager.setPersistenceManagerFactory
See Also:   JdoTransactionManager.setDataSource
See Also:   javax.jdo.PersistenceManagerFactory.getConnectionFactory
See Also:   LocalPersistenceManagerFactoryBean
See Also:   PersistenceManagerFactoryUtils.getPersistenceManager
See Also:   PersistenceManagerFactoryUtils.releasePersistenceManager
See Also:   JdoTemplate
See Also:   TransactionAwarePersistenceManagerFactoryProxy
See Also:   org.springframework.jdbc.datasource.DataSourceUtils.getConnection
See Also:   org.springframework.jdbc.datasource.DataSourceUtils.releaseConnection
See Also:   org.springframework.jdbc.core.JdbcTemplate
See Also:   org.springframework.jdbc.datasource.DataSourceTransactionManager
See Also:   org.springframework.transaction.jta.JtaTransactionManager

If the PersistenceManagerFactory uses a DataSource as connection factory, the DataSource will be autodetected: You can still explictly specify the DataSource, but you don't need to in this case.

A transactional JDBC Connection for this DataSource will be provided to application code accessing this DataSource directly via DataSourceUtils or JdbcTemplate.

The PersistenceManagerFactory specified here should be the target PersistenceManagerFactory to manage transactions for, not a TransactionAwarePersistenceManagerFactoryProxy.

Default implementation delegates to the JdoDialect. May be overridden in subclasses.
Parameters:
  ex - JDOException that occured the corresponding DataAccessException instance
See Also:   JdoDialect.translateException

Creates a default one for the specified PersistenceManagerFactory if none set.

Can be turned off to deliberately ignore an available DataSource, to not expose JDO transactions as JDBC transactions for that DataSource.
See Also:   JdoTransactionManager.setDataSource
See Also:   javax.jdo.PersistenceManagerFactory.getConnectionFactory

If the PersistenceManagerFactory uses a DataSource as connection factory, the DataSource will be autodetected: You can still explictly specify the DataSource, but you don't need to in this case.

A transactional JDBC Connection for this DataSource will be provided to application code accessing this DataSource directly via DataSourceUtils or JdbcTemplate. The Connection will be taken from the JDO PersistenceManager.

Note that you need to use a JDO dialect for a specific JDO provider to allow for exposing JDO transactions as JDBC transactions.

The DataSource specified here should be the target DataSource to manage transactions for, not a TransactionAwareDataSourceProxy. Only data access code may work with TransactionAwareDataSourceProxy, while the transaction manager needs to work on the underlying target DataSource. If there's nevertheless a TransactionAwareDataSourceProxy passed in, it will be unwrapped to extract its target DataSource.
See Also:   JdoTransactionManager.setAutodetectDataSource
See Also:   JdoTransactionManager.setJdoDialect
See Also:   javax.jdo.PersistenceManagerFactory.getConnectionFactory
See Also:   org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy
See Also:   org.springframework.jdbc.datasource.DataSourceUtils
See Also:   org.springframework.jdbc.core.JdbcTemplate

The dialect object can be used to retrieve the underlying JDBC connection and thus allows for exposing JDO transactions as JDBC transactions.
See Also:   JdoDialect.getJdbcConnection

The PersistenceManagerFactory specified here should be the target PersistenceManagerFactory to manage transactions for, not a TransactionAwarePersistenceManagerFactoryProxy. Only data access code may work with TransactionAwarePersistenceManagerFactoryProxy, while the transaction manager needs to work on the underlying target PersistenceManagerFactory.
See Also:   TransactionAwarePersistenceManagerFactoryProxy