Note that isolation level and timeout settings will not get applied unless * an actual new transaction gets started. As only {@link #PROPAGATION_REQUIRED}, * {@link #PROPAGATION_REQUIRES_NEW} and {@link #PROPAGATION_NESTED} can cause * that, it usually doesn't make sense to specify those settings in other cases. * Furthermore, be aware that not all transaction managers will support those * advanced features and thus might throw corresponding exceptions when given * non-default values. * *
The {@link #isReadOnly() read-only flag} applies to any transaction context,
* whether backed by an actual resource transaction or operating non-transactionally
* at the resource level. In the latter case, the flag will only apply to managed
* resources within the application, such as a Hibernate Session.
*
* @author Juergen Hoeller
* @since 08.05.2003
* @see PlatformTransactionManager#getTransaction(TransactionDefinition)
* @see org.springframework.transaction.support.DefaultTransactionDefinition
* @see org.springframework.transaction.interceptor.TransactionAttribute
*/
public interface TransactionDefinition {
/**
* Support a current transaction; create a new one if none exists.
* Analogous to the EJB transaction attribute of the same name.
*
This is typically the default setting of a transaction definition, * and typically defines a transaction synchronization scope. */ int PROPAGATION_REQUIRED = 0; /** * Support a current transaction; execute non-transactionally if none exists. * Analogous to the EJB transaction attribute of the same name. *
NOTE: For transaction managers with transaction synchronization,
* PROPAGATION_SUPPORTS is slightly different from no transaction
* at all, as it defines a transaction scope that synchronization might apply to.
* As a consequence, the same resources (a JDBC Connection, a
* Hibernate Session, etc) will be shared for the entire specified
* scope. Note that the exact behavior depends on the actual synchronization
* configuration of the transaction manager!
*
In general, use PROPAGATION_SUPPORTS with care! In particular, do
* not rely on PROPAGATION_REQUIRED or PROPAGATION_REQUIRES_NEW
* within a PROPAGATION_SUPPORTS scope (which may lead to
* synchronization conflicts at runtime). If such nesting is unavoidable, make sure
* to configure your transaction manager appropriately (typically switching to
* "synchronization on actual transaction").
* @see org.springframework.transaction.support.AbstractPlatformTransactionManager#setTransactionSynchronization
* @see org.springframework.transaction.support.AbstractPlatformTransactionManager#SYNCHRONIZATION_ON_ACTUAL_TRANSACTION
*/
int PROPAGATION_SUPPORTS = 1;
/**
* Support a current transaction; throw an exception if no current transaction
* exists. Analogous to the EJB transaction attribute of the same name.
*
Note that transaction synchronization within a PROPAGATION_MANDATORY
* scope will always be driven by the surrounding transaction.
*/
int PROPAGATION_MANDATORY = 2;
/**
* Create a new transaction, suspending the current transaction if one exists.
* Analogous to the EJB transaction attribute of the same name.
*
NOTE: Actual transaction suspension will not work out-of-the-box
* on all transaction managers. This in particular applies to
* {@link org.springframework.transaction.jta.JtaTransactionManager},
* which requires the javax.transaction.TransactionManager
* to be made available it to it (which is server-specific in standard J2EE).
*
A PROPAGATION_REQUIRES_NEW scope always defines its own
* transaction synchronizations. Existing synchronizations will be suspended
* and resumed appropriately.
* @see org.springframework.transaction.jta.JtaTransactionManager#setTransactionManager
*/
int PROPAGATION_REQUIRES_NEW = 3;
/**
* Do not support a current transaction; rather always execute non-transactionally.
* Analogous to the EJB transaction attribute of the same name.
*
NOTE: Actual transaction suspension will not work out-of-the-box
* on all transaction managers. This in particular applies to
* {@link org.springframework.transaction.jta.JtaTransactionManager},
* which requires the javax.transaction.TransactionManager
* to be made available it to it (which is server-specific in standard J2EE).
*
Note that transaction synchronization is not available within a
* PROPAGATION_NOT_SUPPORTED scope. Existing synchronizations
* will be suspended and resumed appropriately.
* @see org.springframework.transaction.jta.JtaTransactionManager#setTransactionManager
*/
int PROPAGATION_NOT_SUPPORTED = 4;
/**
* Do not support a current transaction; throw an exception if a current transaction
* exists. Analogous to the EJB transaction attribute of the same name.
*
Note that transaction synchronization is not available within a
* PROPAGATION_NEVER scope.
*/
int PROPAGATION_NEVER = 5;
/**
* Execute within a nested transaction if a current transaction exists,
* behave like {@link #PROPAGATION_REQUIRED} else. There is no analogous
* feature in EJB.
*
NOTE: Actual creation of a nested transaction will only work on specific * transaction managers. Out of the box, this only applies to the JDBC * {@link org.springframework.jdbc.datasource.DataSourceTransactionManager} * when working on a JDBC 3.0 driver. Some JTA providers might support * nested transactions as well. * @see org.springframework.jdbc.datasource.DataSourceTransactionManager */ int PROPAGATION_NESTED = 6; /** * Use the default isolation level of the underlying datastore. * All other levels correspond to the JDBC isolation levels. * @see java.sql.Connection */ int ISOLATION_DEFAULT = -1; /** * Indicates that dirty reads, non-repeatable reads and phantom reads * can occur. *
This level allows a row changed by one transaction to be read by * another transaction before any changes in that row have been committed * (a "dirty read"). If any of the changes are rolled back, the second * transaction will have retrieved an invalid row. * @see java.sql.Connection#TRANSACTION_READ_UNCOMMITTED */ int ISOLATION_READ_UNCOMMITTED = Connection.TRANSACTION_READ_UNCOMMITTED; /** * Indicates that dirty reads are prevented; non-repeatable reads and * phantom reads can occur. *
This level only prohibits a transaction from reading a row * with uncommitted changes in it. * @see java.sql.Connection#TRANSACTION_READ_COMMITTED */ int ISOLATION_READ_COMMITTED = Connection.TRANSACTION_READ_COMMITTED; /** * Indicates that dirty reads and non-repeatable reads are prevented; * phantom reads can occur. *
This level prohibits a transaction from reading a row with * uncommitted changes in it, and it also prohibits the situation * where one transaction reads a row, a second transaction alters * the row, and the first transaction rereads the row, getting * different values the second time (a "non-repeatable read"). * @see java.sql.Connection#TRANSACTION_REPEATABLE_READ */ int ISOLATION_REPEATABLE_READ = Connection.TRANSACTION_REPEATABLE_READ; /** * Indicates that dirty reads, non-repeatable reads and phantom reads * are prevented. *
This level includes the prohibitions in
* {@link #ISOLATION_REPEATABLE_READ} and further prohibits the
* situation where one transaction reads all rows that satisfy a
* WHERE condition, a second transaction inserts a
* row that satisfies that WHERE condition, and the
* first transaction rereads for the same condition, retrieving
* the additional "phantom" row in the second read.
* @see java.sql.Connection#TRANSACTION_SERIALIZABLE
*/
int ISOLATION_SERIALIZABLE = Connection.TRANSACTION_SERIALIZABLE;
/**
* Use the default timeout of the underlying transaction system,
* or none if timeouts are not supported.
*/
int TIMEOUT_DEFAULT = -1;
/**
* Return the propagation behavior.
*
Must return one of the PROPAGATION_XXX constants
* defined on {@link TransactionDefinition this interface}.
* @return the propagation behavior
* @see #PROPAGATION_REQUIRED
* @see org.springframework.transaction.support.TransactionSynchronizationManager#isActualTransactionActive()
*/
int getPropagationBehavior();
/**
* Return the isolation level.
*
Must return one of the ISOLATION_XXX constants
* defined on {@link TransactionDefinition this interface}.
*
Only makes sense in combination with {@link #PROPAGATION_REQUIRED} * or {@link #PROPAGATION_REQUIRES_NEW}. *
Note that a transaction manager that does not support custom * isolation levels will throw an exception when given any other level * than {@link #ISOLATION_DEFAULT}. * @return the isolation level */ int getIsolationLevel(); /** * Return the transaction timeout. *
Must return a number of seconds, or {@link #TIMEOUT_DEFAULT}. *
Only makes sense in combination with {@link #PROPAGATION_REQUIRED} * or {@link #PROPAGATION_REQUIRES_NEW}. *
Note that a transaction manager that does not support timeouts * will throw an exception when given any other timeout than * {@link #TIMEOUT_DEFAULT}. * @return the transaction timeout */ int getTimeout(); /** * Return whether to optimize as a read-only transaction. *
The read-only flag applies to any transaction context, whether
* backed by an actual resource transaction
* ({@link #PROPAGATION_REQUIRED}/{@link #PROPAGATION_REQUIRES_NEW}) or
* operating non-transactionally at the resource level
* ({@link #PROPAGATION_SUPPORTS}). In the latter case, the flag will
* only apply to managed resources within the application, such as a
* Hibernate Session.
*
This just serves as a hint for the actual transaction subsystem;
* it will not necessarily cause failure of write access attempts.
* A transaction manager that cannot interpret the read-only hint will
* not throw an exception when asked for a read-only transaction.
* @return true if the transaction is to be optimized as read-only
* @see org.springframework.transaction.support.TransactionSynchronization#beforeCommit(boolean)
* @see org.springframework.transaction.support.TransactionSynchronizationManager#isCurrentTransactionReadOnly()
*/
boolean isReadOnly();
/**
* Return the name of this transaction. Can be null.
*
This will be used as the transaction name to be shown in a * transaction monitor, if applicable (for example, WebLogic's). *
In case of Spring's declarative transactions, the exposed name
* must (and will) be the
* fully-qualified class name + "." + method name
* (by default).
* @return the name of this transaction
* @see org.springframework.transaction.interceptor.TransactionAspectSupport
* @see org.springframework.transaction.support.TransactionSynchronizationManager#getCurrentTransactionName()
*/
String getName();
}