org.datanucleus.store.rdbms.adapter

Class DatastoreAdapterFactory

java.lang.Object

org.datanucleus.store.rdbms.adapter.DatastoreAdapterFactory

public class DatastoreAdapterFactory
extends Object

Factory of RDBMS datastore adapters. Acts as a registry of adapters to RDBMS that can be selected for use. Uses a singleton pattern, and the factory can be accessed using the getInstance() method.

Autodetection

Provides a level of autodetection of the adapter to use for a particular RDBMS. It uses the DatabaseMetaData to extract the "product name" and matches this against a series of "adapter aliases" that we define internally or that can be contributed by plugins that extend the org.datanucleus.store.rdbms.datastoreadapter extension point. These extension can define a priority, so if multiple adapter match for the given database connection the one with the highest priority is chosen.

Specification of adapter class

You can call getDatastoreAdapter(ClassLoaderResolver, Connection, String, PluginManager) passing the adapter class name directly if you know which you want to use. This allows for user-defined database adapters.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	DatastoreAdapterFactory() Protected constructor to prevent outside instantiation

Method Summary

Modifier and Type	Method and Description
protected Class	getAdapterClass(org.datanucleus.plugin.PluginManager pluginMgr, String adapterClassName, String productName, org.datanucleus.ClassLoaderResolver clr) Accessor for the adapter class for a specified datastore product.
DatastoreAdapter	getDatastoreAdapter(org.datanucleus.ClassLoaderResolver clr, Connection conn, String adapterClassName, org.datanucleus.plugin.PluginManager pluginMgr) Accessor for an adapter, given a Connection to the datastore.
static DatastoreAdapterFactory	getInstance() Accessor for the RDBMSAdapterFactory.
protected DatastoreAdapter	getNewDatastoreAdapter(org.datanucleus.ClassLoaderResolver clr, DatabaseMetaData metadata, String adapterClassName, org.datanucleus.plugin.PluginManager pluginMgr) Accessor for the adapter for a specified datastore product.

Methods inherited from class java.lang.Object

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

Constructor Detail

DatastoreAdapterFactory

protected DatastoreAdapterFactory()

Protected constructor to prevent outside instantiation

Method Detail

getInstance

public static DatastoreAdapterFactory getInstance()

Accessor for the RDBMSAdapterFactory.

Returns:

The manager of type information

getDatastoreAdapter

public DatastoreAdapter getDatastoreAdapter(org.datanucleus.ClassLoaderResolver clr,
                                            Connection conn,
                                            String adapterClassName,
                                            org.datanucleus.plugin.PluginManager pluginMgr)
                                     throws SQLException

Accessor for an adapter, given a Connection to the datastore.

Parameters:

clr - ClassLoader resolver for resolving the adapter class

conn - The Connection

adapterClassName - Name of the class of the database adapter to use

pluginMgr - the Plug-in manager

Returns:

The database adapter for this connection.

Throws:

SQLException - Thrown if a DB error occurs.

getNewDatastoreAdapter

protected DatastoreAdapter getNewDatastoreAdapter(org.datanucleus.ClassLoaderResolver clr,
                                                  DatabaseMetaData metadata,
                                                  String adapterClassName,
                                                  org.datanucleus.plugin.PluginManager pluginMgr)

Accessor for the adapter for a specified datastore product.

Parameters:

clr - ClassLoader resolver for resolving the adapter class

metadata - Database MetaData for the RDBMS

adapterClassName - Name of the class of the database adapter (null implies use autodetect)

pluginMgr - the Plug-in manager

Returns:

Instance of the database adapter

getAdapterClass

protected Class getAdapterClass(org.datanucleus.plugin.PluginManager pluginMgr,
                                String adapterClassName,
                                String productName,
                                org.datanucleus.ClassLoaderResolver clr)

Accessor for the adapter class for a specified datastore product.

Parameters:

pluginMgr - the Plug-in manager

adapterClassName - Name of the class of the database adapter (null implies use autodetect)

productName - the database product name

clr - ClassLoader resolver for resolving the adapter class

Returns:

the adapter class