org.exolab.castor.jdo.engine
Class LocalDatabaseImpl

java.lang.Object
  org.exolab.castor.jdo.engine.AbstractDatabaseImpl
      org.exolab.castor.jdo.engine.LocalDatabaseImpl

All Implemented Interfaces:

Database

public class LocalDatabaseImpl
extends AbstractDatabaseImpl

An implementation of the JDO Database interface supporting explicit local transaction demarcation.

Version:

$Revision: 8347 $ $Date: 2006-04-10 16:39:24 -0600 (Mon, 10 Apr 2006) $

Author:

Assaf Arkin, Bruce Snyder, Werner Guttmann

Field Summary

Fields inherited from class org.exolab.castor.jdo.engine.AbstractDatabaseImpl

_autoStore, _callback, _classLoader, _ctx, _dbName, _instanceFactory, _lockTimeout, _scope

Fields inherited from interface org.exolab.castor.jdo.Database

DbLocked, DBLOCKED, Exclusive, EXCLUSIVE, ReadOnly, READONLY, Shared, SHARED

Constructor Summary

LocalDatabaseImpl(String dbName, int lockTimeout, CallbackInterceptor callback, InstanceFactory instanceFactory, ClassLoader classLoader, boolean autoStore)
Creates an instance of this class.

Method Summary

void	begin() Begin a new transaction.
void	close() Closes the database.
void	commit() Commits and closes the transaction.
protected void	finalize() Overrides Object.finalize().
Connection	getJdbcConnection() Gets the underlying JDBC connection.
void	rollback() Rolls back and closes the transaction.

Methods inherited from class org.exolab.castor.jdo.engine.AbstractDatabaseImpl

create, getCacheManager, getClassLoader, getCurrentTransaction, getDatabaseName, getIdentity, getNamedQuery, getNativeQuery, getOQLQuery, getOQLQuery, getQuery, getScope, getTransaction, isActive, isAutoStore, isClosed, isLocked, isPersistent, load, load, load, loadSynchronizables, lock, registerSynchronizables, remove, setAutoStore, toString, unregisterSynchronizables, update

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

LocalDatabaseImpl

public LocalDatabaseImpl(String dbName,
                         int lockTimeout,
                         CallbackInterceptor callback,
                         InstanceFactory instanceFactory,
                         ClassLoader classLoader,
                         boolean autoStore)
                  throws DatabaseNotFoundException

Creates an instance of this class.

Parameters:

dbName - database name

lockTimeout - Lock timeout

callback - CallbackInterceptor instance

instanceFactory - Instance factory.

classLoader - Current class loader

autoStore - Indicates whether to use 'auto-storing'

Throws:

DatabaseNotFoundException - If the specified database configuration cannot be found.

Method Detail

close

public void close()
           throws PersistenceException

Description copied from class: AbstractDatabaseImpl

Closes the database. If a client transaction is in progress the transaction will be rolled back and an exception thrown. If an app-server transaction is in progress, the transaction will commit/rollback when triggered by the application server.

Specified by:

close in interface Database

Specified by:

close in class AbstractDatabaseImpl

Throws:

PersistenceException - An error occured while attempting to close the database

See Also:

Database.close()

finalize

protected void finalize()
                 throws Throwable

Overrides Object.finalize(). Outputs a warning message to the logs if the current DatabaseImpl instance still has valid scope. In this condition - a condition that ideally should not occur at all - we close the instance as well to free up resources.

Overrides:

finalize in class Object

Throws:

Throwable

See Also:

Object.finalize()

begin

public void begin()
           throws PersistenceException

Description copied from class: AbstractDatabaseImpl

Begin a new transaction. A transaction must be open in order to query and persist objects.

Specified by:

begin in interface Database

Specified by:

begin in class AbstractDatabaseImpl

Throws:

PersistenceException - A transaction is already open on this database, or an error reported by the persistence engine

commit

public void commit()
            throws TransactionNotInProgressException,
                   TransactionAbortedException

Description copied from class: AbstractDatabaseImpl

Commits and closes the transaction. All changes made to persistent objects during the transaction are made persistent; objects created during the transaction are made durable; and, objects removed during the transaction are removed from the database.

In other words, any modifications to any data objects which are queried/loaded/created/update to this database is automatically stored to the database and visible to subsequence transactions. (ie. update is solely used for long transaction support and should not be called for any data object queried/loaded/created in the this transaction.)

If the transaction cannot commit, the entire transaction rolls back and a TransactionAbortedException exception is thrown.

After this method returns, the transaction is closed and all persistent objects are transient. Using Database.begin() to open a new transaction will not restore objects to their persistent stage.

Specified by:

commit in interface Database

Specified by:

commit in class AbstractDatabaseImpl

Throws:

TransactionNotInProgressException - Method called while transaction is not in progress

TransactionAbortedException - The transaction cannot commit and has been rolled back

rollback

public void rollback()
              throws TransactionNotInProgressException

Description copied from class: AbstractDatabaseImpl

Rolls back and closes the transaction. All changes made to persistent objects during the transaction are lost, objects created during the transaction are not made durable and objects removed during the transaction continue to exist.

Specified by:

rollback in interface Database

Specified by:

rollback in class AbstractDatabaseImpl

Throws:

TransactionNotInProgressException - Method called while transaction is not in progress

See Also:

Database.rollback()

getJdbcConnection

public Connection getJdbcConnection()
                             throws PersistenceException

Description copied from class: AbstractDatabaseImpl

Gets the underlying JDBC connection. This is for advanced use only. Please make sure that you never close this Connection instance, as it will be closed by Castor.

Specified by:

getJdbcConnection in interface Database

Specified by:

getJdbcConnection in class AbstractDatabaseImpl

Returns:

the underlying JDBC connection, if present; otherwise null

Throws:

PersistenceException - If the underlying JDBC connection cannot be obtained.

See Also:

Database.getJdbcConnection()