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JpaTransactionManager (Spring Framework API 2.0) - Spring Framework 2.0.5 API 文档英文版

The Spring Framework

org.springframework.orm.jpa
Class JpaTransactionManager

java.lang.Object
  extended by org.springframework.transaction.support.AbstractPlatformTransactionManager
      extended by org.springframework.orm.jpa.JpaTransactionManager
All Implemented Interfaces:
Serializable, InitializingBean, PlatformTransactionManager, ResourceTransactionManager

public class JpaTransactionManager
extends AbstractPlatformTransactionManager
implements ResourceTransactionManager, InitializingBean

PlatformTransactionManager implementation for a single JPA EntityManagerFactory. Binds a JPA EntityManager from the specified factory to the thread, potentially allowing for one thread-bound EntityManager per factory. SharedEntityManagerCreator and JpaTemplate are aware of thread-bound entity managers and participate in such transactions automatically. Using either is required for JPA access code supporting this transaction management mechanism.

This transaction manager is appropriate for applications that use a single JPA EntityManagerFactory for transactional data access. JTA (usually through JtaTransactionManager) is necessary for accessing multiple transactional resources within the same transaction. Note that you need to configure your JPA 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 JPA and services which use plain JDBC (without being aware of JPA)! Application code needs to stick to the same simple Connection lookup pattern as with DataSourceTransactionManager (i.e. DataSourceUtils.getConnection(javax.sql.DataSource) or going through a TransactionAwareDataSourceProxy). Note that this requires a vendor-specific JpaDialect to be configured.

Note: To be able to register a DataSource's Connection for plain JDBC code, this instance needs to be aware of the DataSource (setDataSource(javax.sql.DataSource)). The given DataSource should obviously match the one used by the given EntityManagerFactory. This transaction manager will autodetect the DataSource used as known connection factory of the EntityManagerFactory, 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 AbstractPlatformTransactionManager.setNestedTransactionAllowed(boolean) "nestedTransactionAllowed"} flag defaults to "false", though, as nested transactions will just apply to the JDBC Connection, not to the JPA EntityManager 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 JPA transactions (provided that your JDBC driver supports Savepoints). Note that JPA itself does not support nested transactions! Hence, do not expect JPA access code to semantically participate in a nested transaction.

Since:
2.0
Author:
Juergen Hoeller
See Also:
setEntityManagerFactory(javax.persistence.EntityManagerFactory), setDataSource(javax.sql.DataSource), LocalEntityManagerFactoryBean, JpaTemplate.execute(org.springframework.orm.jpa.JpaCallback), SharedEntityManagerBean, DataSourceUtils.getConnection(javax.sql.DataSource), DataSourceUtils.releaseConnection(java.sql.Connection, javax.sql.DataSource), JdbcTemplate, DataSourceTransactionManager, JtaTransactionManager, Serialized Form

Field Summary
 
Fields inherited from class org.springframework.transaction.support.AbstractPlatformTransactionManager
logger, SYNCHRONIZATION_ALWAYS, SYNCHRONIZATION_NEVER, SYNCHRONIZATION_ON_ACTUAL_TRANSACTION
 
Constructor Summary
JpaTransactionManager()
          Create a new JpaTransactionManager instance.
JpaTransactionManager(javax.persistence.EntityManagerFactory emf)
          Create a new JpaTransactionManager instance.
 
Method Summary
 void afterPropertiesSet()
          Eagerly initialize the JPA dialect, creating a default one for the specified EntityManagerFactory if none set.
protected  javax.persistence.EntityManager createEntityManagerForTransaction()
          Create a JPA EntityManager to be used for a transaction.
protected  void doBegin(Object transaction, TransactionDefinition definition)
          Begin a new transaction with semantics according to the given transaction definition.
protected  void doCleanupAfterCompletion(Object transaction)
          Cleanup resources after transaction completion.
protected  void doCommit(DefaultTransactionStatus status)
          Perform an actual commit of the given transaction.
protected  Object doGetTransaction()
          Return a transaction object for the current transaction state.
protected  void doResume(Object transaction, Object suspendedResources)
          Resume the resources of the current transaction.
protected  void doRollback(DefaultTransactionStatus status)
          Perform an actual rollback of the given transaction.
protected  void doSetRollbackOnly(DefaultTransactionStatus status)
          Set the given transaction rollback-only.
protected  Object doSuspend(Object transaction)
          Suspend the resources of the current transaction.
 DataSource getDataSource()
          Return the JDBC DataSource that this instance manages transactions for.
 javax.persistence.EntityManagerFactory getEntityManagerFactory()
          Return the EntityManagerFactory that this instance should manage transactions for.
 JpaDialect getJpaDialect()
          Return the JPA dialect to use for this transaction manager.
 Map getJpaPropertyMap()
          Allow Map access to the JPA properties to be passed to the persistence provider, with the option to add or override specific entries.
 Object getResourceFactory()
          Return the resource factory that this transaction manager operates on, e.g. a JDBC DataSource or a JMS ConnectionFactory.
protected  boolean isExistingTransaction(Object transaction)
          Check if the given transaction object indicates an existing transaction (that is, a transaction which has already started).
 void setDataSource(DataSource dataSource)
          Set the JDBC DataSource that this instance should manage transactions for.
 void setEntityManagerFactory(javax.persistence.EntityManagerFactory emf)
          Set the EntityManagerFactory that this instance should manage transactions for.
 void setJpaDialect(JpaDialect jpaDialect)
          Set the JPA dialect to use for this transaction manager.
 void setJpaProperties(Properties jpaProperties)
          Specify JPA properties, to be passed into EntityManagerFactory.createEntityManager(Map) (if any).
 void setJpaPropertyMap(Map jpaProperties)
          Specify JPA properties as a Map, to be passed into EntityManagerFactory.createEntityManager(Map) (if any).
protected  boolean shouldCommitOnGlobalRollbackOnly()
          This implementation returns "true": a JPA commit will properly handle transactions that have been marked rollback-only at a global level.
 
Methods inherited from class org.springframework.transaction.support.AbstractPlatformTransactionManager
commit, determineTimeout, getDefaultTimeout, getTransaction, getTransactionSynchronization, invokeAfterCompletion, isFailEarlyOnGlobalRollbackOnly, isGlobalRollbackOnParticipationFailure, isNestedTransactionAllowed, isRollbackOnCommitFailure, newTransactionStatus, registerAfterCompletionWithExistingTransaction, resume, rollback, setDefaultTimeout, setFailEarlyOnGlobalRollbackOnly, setGlobalRollbackOnParticipationFailure, setNestedTransactionAllowed, setRollbackOnCommitFailure, setTransactionSynchronization, setTransactionSynchronizationName, suspend, triggerBeforeCommit, triggerBeforeCompletion, useSavepointForNestedTransaction
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.springframework.transaction.PlatformTransactionManager
commit, getTransaction, rollback
 

Constructor Detail

JpaTransactionManager

public JpaTransactionManager()
Create a new JpaTransactionManager instance. A EntityManagerFactory has to be set to be able to use it.

See Also:
setEntityManagerFactory(javax.persistence.EntityManagerFactory)

JpaTransactionManager

public JpaTransactionManager(javax.persistence.EntityManagerFactory emf)
Create a new JpaTransactionManager instance.

Parameters:
emf - EntityManagerFactory to manage transactions for
Method Detail

setEntityManagerFactory

public void setEntityManagerFactory(javax.persistence.EntityManagerFactory emf)
Set the EntityManagerFactory that this instance should manage transactions for.


getEntityManagerFactory

public javax.persistence.EntityManagerFactory getEntityManagerFactory()
Return the EntityManagerFactory that this instance should manage transactions for.


setJpaProperties

public void setJpaProperties(Properties jpaProperties)
Specify JPA properties, to be passed into EntityManagerFactory.createEntityManager(Map) (if any).

Can be populated with a String "value" (parsed via PropertiesEditor) or a "props" element in XML bean definitions.

See Also:
EntityManagerFactory.createEntityManager(java.util.Map)

setJpaPropertyMap

public void setJpaPropertyMap(Map jpaProperties)
Specify JPA properties as a Map, to be passed into EntityManagerFactory.createEntityManager(Map) (if any).

Can be populated with a "map" or "props" element in XML bean definitions.

See Also:
EntityManagerFactory.createEntityManager(java.util.Map)

getJpaPropertyMap

public Map getJpaPropertyMap()
Allow Map access to the JPA properties to be passed to the persistence provider, with the option to add or override specific entries.

Useful for specifying entries directly, for example via "jpaPropertyMap[myKey]".


setDataSource

public void setDataSource(DataSource dataSource)
Set the JDBC DataSource that this instance should manage transactions for. The DataSource should match the one used by the JPA EntityManagerFactory: for example, you could specify the same JNDI DataSource for both.

If the EntityManagerFactory uses a known 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 JPA EntityManager.

Note that you need to use a JPA dialect for a specific JPA implementation to allow for exposing JPA 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:
EntityManagerFactoryInfo.getDataSource(), setJpaDialect(org.springframework.orm.jpa.JpaDialect), TransactionAwareDataSourceProxy, DataSourceUtils, JdbcTemplate

getDataSource

public DataSource getDataSource()
Return the JDBC DataSource that this instance manages transactions for.


setJpaDialect

public void setJpaDialect(JpaDialect jpaDialect)
Set the JPA dialect to use for this transaction manager. Used for vendor-specific transaction management and JDBC connection exposure.

If the EntityManagerFactory uses a known JpaDialect, it will be autodetected: You can still explictly specify the DataSource, but you don't need to in this case.

The dialect object can be used to retrieve the underlying JDBC connection and thus allows for exposing JPA transactions as JDBC transactions.

See Also:
EntityManagerFactoryInfo.getJpaDialect(), JpaDialect.beginTransaction(javax.persistence.EntityManager, org.springframework.transaction.TransactionDefinition), JpaDialect.getJdbcConnection(javax.persistence.EntityManager, boolean)

getJpaDialect

public JpaDialect getJpaDialect()
Return the JPA dialect to use for this transaction manager.


afterPropertiesSet

public void afterPropertiesSet()
Eagerly initialize the JPA dialect, creating a default one for the specified EntityManagerFactory if none set. Auto-detect the EntityManagerFactory's DataSource, if any.

Specified by:
afterPropertiesSet in interface InitializingBean

getResourceFactory

public Object getResourceFactory()
Description copied from interface: ResourceTransactionManager
Return the resource factory that this transaction manager operates on, e.g. a JDBC DataSource or a JMS ConnectionFactory.

This target resource factory is usually used as resource key for TransactionSynchronizationManager's resource bindings per thread.

Specified by:
getResourceFactory in interface ResourceTransactionManager
Returns:
the target resource factory (never null)
See Also:
TransactionSynchronizationManager.bindResource(java.lang.Object, java.lang.Object), TransactionSynchronizationManager.getResource(java.lang.Object)

doGetTransaction

protected Object doGetTransaction()
Description copied from class: AbstractPlatformTransactionManager
Return a transaction object for the current transaction state.

The returned object will usually be specific to the concrete transaction manager implementation, carrying corresponding transaction state in a modifiable fashion. This object will be passed into the other template methods (e.g. doBegin and doCommit), either directly or as part of a DefaultTransactionStatus instance.

The returned object should contain information about any existing transaction, that is, a transaction that has already started before the current getTransaction call on the transaction manager. Consequently, a doGetTransaction implementation will usually look for an existing transaction and store corresponding state in the returned transaction object.

Specified by:
doGetTransaction in class AbstractPlatformTransactionManager
Returns:
the current transaction object
See Also:
AbstractPlatformTransactionManager.doBegin(java.lang.Object, org.springframework.transaction.TransactionDefinition), AbstractPlatformTransactionManager.doCommit(org.springframework.transaction.support.DefaultTransactionStatus), AbstractPlatformTransactionManager.doRollback(org.springframework.transaction.support.DefaultTransactionStatus), DefaultTransactionStatus.getTransaction()

isExistingTransaction

protected boolean isExistingTransaction(Object transaction)
Description copied from class: AbstractPlatformTransactionManager
Check if the given transaction object indicates an existing transaction (that is, a transaction which has already started).

The result will be evaluated according to the specified propagation behavior for the new transaction. An existing transaction might get suspended (in case of PROPAGATION_REQUIRES_NEW), or the new transaction might participate in the existing one (in case of PROPAGATION_REQUIRED).

The default implementation returns false, assuming that participating in existing transactions is generally not supported. Subclasses are of course encouraged to provide such support.

Overrides:
isExistingTransaction in class AbstractPlatformTransactionManager
Parameters:
transaction - transaction object returned by doGetTransaction
Returns:
if there is an existing transaction
See Also:
AbstractPlatformTransactionManager.doGetTransaction()

doBegin

protected void doBegin(Object transaction,
                       TransactionDefinition definition)
Description copied from class: AbstractPlatformTransactionManager
Begin a new transaction with semantics according to the given transaction definition. Does not have to care about applying the propagation behavior, as this has already been handled by this abstract manager.

This method gets called when the transaction manager has decided to actually start a new transaction. Either there wasn't any transaction before, or the previous transaction has been suspended.

A special scenario is a nested transaction without savepoint: If useSavepointForNestedTransaction() returns "false", this method will be called to start a nested transaction when necessary. In such a context, there will be an active transaction: The implementation of this method has to detect this and start an appropriate nested transaction.

Specified by:
doBegin in class AbstractPlatformTransactionManager
Parameters:
transaction - transaction object returned by doGetTransaction
definition - TransactionDefinition instance, describing propagation behavior, isolation level, read-only flag, timeout, and transaction name

createEntityManagerForTransaction

protected javax.persistence.EntityManager createEntityManagerForTransaction()
Create a JPA EntityManager to be used for a transaction.

The default implementation checks whether the EntityManagerFactory is a Spring proxy and unwraps it first.

See Also:
EntityManagerFactory.createEntityManager(), EntityManagerFactoryInfo.getNativeEntityManagerFactory()

doSuspend

protected Object doSuspend(Object transaction)
Description copied from class: AbstractPlatformTransactionManager
Suspend the resources of the current transaction. Transaction synchronization will already have been suspended.

The default implementation throws a TransactionSuspensionNotSupportedException, assuming that transaction suspension is generally not supported.

Overrides:
doSuspend in class AbstractPlatformTransactionManager
Parameters:
transaction - transaction object returned by doGetTransaction
Returns:
an object that holds suspended resources (will be kept unexamined for passing it into doResume)
See Also:
AbstractPlatformTransactionManager.doResume(java.lang.Object, java.lang.Object)

doResume

protected void doResume(Object transaction,
                        Object suspendedResources)
Description copied from class: AbstractPlatformTransactionManager
Resume the resources of the current transaction. Transaction synchronization will be resumed afterwards.

The default implementation throws a TransactionSuspensionNotSupportedException, assuming that transaction suspension is generally not supported.

Overrides:
doResume in class AbstractPlatformTransactionManager
Parameters:
transaction - transaction object returned by doGetTransaction
suspendedResources - the object that holds suspended resources, as returned by doSuspend
See Also:
AbstractPlatformTransactionManager.doSuspend(java.lang.Object)

shouldCommitOnGlobalRollbackOnly

protected boolean shouldCommitOnGlobalRollbackOnly()
This implementation returns "true": a JPA commit will properly handle transactions that have been marked rollback-only at a global level.

Overrides:
shouldCommitOnGlobalRollbackOnly in class AbstractPlatformTransactionManager
See Also:
AbstractPlatformTransactionManager.doCommit(org.springframework.transaction.support.DefaultTransactionStatus), DefaultTransactionStatus.isGlobalRollbackOnly(), AbstractTransactionStatus.isLocalRollbackOnly(), TransactionStatus.setRollbackOnly(), UnexpectedRollbackException, UserTransaction.commit(), RollbackException

doCommit

protected void doCommit(DefaultTransactionStatus status)
Description copied from class: AbstractPlatformTransactionManager
Perform an actual commit of the given transaction.

An implementation does not need to check the "new transaction" flag or the rollback-only flag; this will already have been handled before. Usually, a straight commit will be performed on the transaction object contained in the passed-in status.

Specified by:
doCommit in class AbstractPlatformTransactionManager
Parameters:
status - the status representation of the transaction
See Also:
DefaultTransactionStatus.getTransaction()

doRollback

protected void doRollback(DefaultTransactionStatus status)
Description copied from class: AbstractPlatformTransactionManager
Perform an actual rollback of the given transaction.

An implementation does not need to check the "new transaction" flag; this will already have been handled before. Usually, a straight rollback will be performed on the transaction object contained in the passed-in status.

Specified by:
doRollback in class AbstractPlatformTransactionManager
Parameters:
status - the status representation of the transaction
See Also:
DefaultTransactionStatus.getTransaction()

doSetRollbackOnly

protected void doSetRollbackOnly(DefaultTransactionStatus status)
Description copied from class: AbstractPlatformTransactionManager
Set the given transaction rollback-only. Only called on rollback if the current transaction participates in an existing one.

The default implementation throws an IllegalTransactionStateException, assuming that participating in existing transactions is generally not supported. Subclasses are of course encouraged to provide such support.

Overrides:
doSetRollbackOnly in class AbstractPlatformTransactionManager
Parameters:
status - the status representation of the transaction

doCleanupAfterCompletion

protected void doCleanupAfterCompletion(Object transaction)
Description copied from class: AbstractPlatformTransactionManager
Cleanup resources after transaction completion.

Called after doCommit and doRollback execution, on any outcome. The default implementation does nothing.

Should not throw any exceptions but just issue warnings on errors.

Overrides:
doCleanupAfterCompletion in class AbstractPlatformTransactionManager
Parameters:
transaction - transaction object returned by doGetTransaction

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