org.datanucleus.store.connection

Class ConnectionManagerImpl

java.lang.Object

org.datanucleus.store.connection.ConnectionManagerImpl

All Implemented Interfaces:

ConnectionManager

public class ConnectionManagerImpl
extends Object
implements ConnectionManager

Manager of connections for a datastore, allowing ManagedConnection pooling, enlistment in transaction. The pool caches one connection per ExecutionContext per factory, consequently there will be 0-2 connections pooled per ExecutionContext (0 if none in use, 1 if just primary factory, 1 if primary+secondary factory). The "allocateConnection" method can create connections and enlist them (like most normal persistence operations need) or create a connection and return it without enlisting it into a transaction, for example on a read-only operation, or when running non-transactional, or to get schema information.

Connections can be locked per ExecutionContext basis. Locking of connections is used to handle the connection over to the user application. A locked connection denies any further access to the datastore, until the user application unlock it.

Constructor Summary

Constructors

Constructor and Description
ConnectionManagerImpl(PersistenceNucleusContext context) Constructor.

Method Summary

Modifier and Type	Method and Description
ManagedConnection	allocateConnection(ConnectionFactory factory, ExecutionContext ec, Transaction transaction, Map options) Method to return a connection for this ExecutionContext.
void	closeAllConnections(ConnectionFactory factory, ExecutionContext ec) Method to close all pooled connections for the specified key of the specified factory.
void	disableConnectionPool() Disable binding objects to ExecutionContext references, so automatically disables the connection pooling
ConnectionFactory	lookupConnectionFactory(String name) Method to lookup a connection factory and create it if not yet existing.
void	registerConnectionFactory(String name, ConnectionFactory factory) Method to register a connection factory under a name.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConnectionManagerImpl

public ConnectionManagerImpl(PersistenceNucleusContext context)

Constructor.

Parameters:

context - Context for this manager.

Method Detail

closeAllConnections

public void closeAllConnections(ConnectionFactory factory,
                                ExecutionContext ec)

Method to close all pooled connections for the specified key of the specified factory.

Specified by:

closeAllConnections in interface ConnectionManager

Parameters:

factory - The factory

ec - The key in the pool

allocateConnection

public ManagedConnection allocateConnection(ConnectionFactory factory,
                                            ExecutionContext ec,
                                            Transaction transaction,
                                            Map options)

Method to return a connection for this ExecutionContext. If a connection for the ExecutionContext exists in the cache will return it. If no connection exists will create a new one using the ConnectionFactory.

Specified by:

allocateConnection in interface ConnectionManager

Parameters:

factory - ConnectionFactory it relates to

ec - Key in the pool

options - Options for the connection (e.g isolation). These will override those of the txn itself

transaction - The transaction

Returns:

The ManagedConnection

lookupConnectionFactory

public ConnectionFactory lookupConnectionFactory(String name)

Method to lookup a connection factory and create it if not yet existing.

Specified by:

lookupConnectionFactory in interface ConnectionManager

Parameters:

name - The lookup name "e.g "jdbc/tx"

Returns:

The connection factory

registerConnectionFactory

public void registerConnectionFactory(String name,
                                      ConnectionFactory factory)

Method to register a connection factory under a name.

Specified by:

registerConnectionFactory in interface ConnectionManager

Parameters:

name - The lookup name "e.g "jdbc/tx"

factory - The connection factory

disableConnectionPool

public void disableConnectionPool()

Disable binding objects to ExecutionContext references, so automatically disables the connection pooling

Specified by:

disableConnectionPool in interface ConnectionManager