package org.apache.torque;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.apache.commons.configuration.Configuration;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.torque.adapter.DB;
import org.apache.torque.adapter.DBFactory;
import org.apache.torque.dsfactory.DataSourceFactory;
import org.apache.torque.manager.AbstractBaseManager;
import org.apache.torque.map.DatabaseMap;
import org.apache.torque.map.MapBuilder;
import org.apache.torque.oid.IDBroker;
import org.apache.torque.oid.IDGeneratorFactory;
/**
* The core of Torque's implementation. Both the classic {@link
* org.apache.torque.Torque} static wrapper and the {@link
* org.apache.torque.avalon.TorqueComponent} <a
* href="http://avalon.apache.org/">Avalon</a> implementation leverage
* this class.
*
* @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
* @author <a href="mailto:magnus@handtolvur.is">Magn�s ��r Torfason</a>
* @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
* @author <a href="mailto:Rafal.Krzewski@e-point.pl">Rafal Krzewski</a>
* @author <a href="mailto:mpoeschl@marmot.at">Martin Poeschl</a>
* @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
* @author <a href="mailto:kschrader@karmalab.org">Kurt Schrader</a>
* @author <a href="mailto:tv@apache.org">Thomas Vandahl</a>
* @version $Id: TorqueInstance.java 500332 2007-01-26 20:30:34Z tfischer $
*/
public class TorqueInstance
{
/** Logging */
private static Log log = LogFactory.getLog(TorqueInstance.class);
/** A constant for <code>default</code>. */
private static final String DEFAULT_NAME = "default";
/** The db name that is specified as the default in the property file */
private String defaultDBName = null;
/**
* The Map which contains all known databases. All iterations over the map
* and other operations where the databaase map needs to stay
* in a defined state must be synchronized to this map.
*/
private Map databases = Collections.synchronizedMap(new HashMap());
/** A repository of Manager instances. */
private Map managers;
/** Torque-specific configuration. */
private Configuration conf;
/** flag to set to true once this class has been initialized */
private boolean isInit = false;
/**
* a flag which indicates whether the DataSourceFactory in the database
* named <code>DEFAULT</code> is a reference to another
* DataSourceFactory. This is important to know when closing the
* DataSourceFactories on shutdown();
*/
private boolean defaultDsfIsReference = false;
/**
* Store mapbuilder classnames for peers that have been referenced prior
* to Torque being initialized. This can happen if torque om/peer objects
* are serialized then unserialized prior to Torque being reinitialized.
* This condition exists in a normal catalina restart.
*/
private Map mapBuilderCache = null;
/**
* Creates a new instance with default configuration.
*
* @see #resetConfiguration()
*/
public TorqueInstance()
{
resetConfiguration();
}
/**
* Initializes this instance of Torque.
*
* @see org.apache.stratum.lifecycle.Initializable
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
private synchronized void initialize() throws TorqueException
{
log.debug("initialize()");
if (isInit)
{
log.debug("Multiple initializations of Torque attempted");
return;
}
if (conf == null || conf.isEmpty())
{
throw new TorqueException("Torque cannot be initialized without "
+ "a valid configuration. Please check the log files "
+ "for further details.");
}
// Now that we have dealt with processing the log4j properties
// that may be contained in the configuration we will make the
// configuration consist only of the remain torque specific
// properties that are contained in the configuration. First
// look for properties that are in the "torque" namespace.
Configuration subConf = conf.subset(Torque.TORQUE_KEY);
if (subConf == null || subConf.isEmpty())
{
String error = ("Invalid configuration. No keys starting with "
+ Torque.TORQUE_KEY
+ " found in configuration");
log.error(error);
throw new TorqueException(error);
}
setConfiguration(subConf);
initDefaultDbName(conf);
initAdapters(conf);
initDataSourceFactories(conf);
// setup manager mappings
initManagerMappings(conf);
isInit = true;
// re-build any MapBuilders that may have gone lost during serialization
synchronized (mapBuilderCache)
{
for (Iterator i = mapBuilderCache.entrySet().iterator(); i.hasNext();)
{
Map.Entry entry = (Map.Entry)i.next();
if (null == entry.getValue())
{
try
{
// create and build the MapBuilder
MapBuilder builder = (MapBuilder) Class.forName((String) entry.getKey()).newInstance();
if (!builder.isBuilt())
{
builder.doBuild();
}
entry.setValue(builder);
}
catch (Exception e)
{
throw new TorqueException(e);
}
}
}
}
}
/**
* Initializes the name of the default database and
* associates the database with the name <code>DEFAULT_NAME</code>
* to the default database.
*
* @param conf the configuration representing the torque section.
* of the properties file.
* @throws TorqueException if the appropriate key is not set.
*/
private void initDefaultDbName(Configuration conf)
throws TorqueException
{
// Determine default database name.
defaultDBName =
conf.getString(
Torque.DATABASE_KEY
+ "."
+ Torque.DEFAULT_KEY);
if (defaultDBName == null)
{
String error = "Invalid configuration: Key "
+ Torque.TORQUE_KEY
+ "."
+ Torque.DATABASE_KEY
+ "."
+ Torque.DEFAULT_KEY
+ " not set";
log.error(error);
throw new TorqueException(error);
}
}
/**
* Reads the adapter settings from the configuration and
* assigns the appropriate database adapters and Id Generators
* to the databases.
*
* @param conf the Configuration representing the torque section of the
* properties file
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
private void initAdapters(Configuration conf)
throws TorqueException
{
log.debug("initAdapters(" + conf + ")");
Configuration c = conf.subset(Torque.DATABASE_KEY);
if (c == null || c.isEmpty())
{
String error = "Invalid configuration : "
+ "No keys starting with "
+ Torque.TORQUE_KEY
+ "."
+ Torque.DATABASE_KEY
+ " found in configuration";
log.error(error);
throw new TorqueException(error);
}
try
{
for (Iterator it = c.getKeys(); it.hasNext();)
{
String key = (String) it.next();
if (key.endsWith(DB.ADAPTER_KEY)
|| key.endsWith(DB.DRIVER_KEY))
{
String adapter = c.getString(key);
String handle = key.substring(0, key.indexOf('.'));
DB db;
db = DBFactory.create(adapter);
// Not supported, try manually defined adapter class
if (db == null)
{
String adapterClassName = c.getString(key + "." + adapter + ".className", null);
db = DBFactory.create(adapter, adapterClassName);
}
Database database = getOrCreateDatabase(handle);
// register the adapter for this name
database.setAdapter(db);
log.debug("Adding " + adapter + " -> "
+ handle + " as Adapter");
// add Id generators
// first make sure that the dtabaseMap exists for the name
// as the idGenerators are still stored in the database map
// TODO: change when the idGenerators are stored in the
// database
getDatabaseMap(handle);
for (int i = 0;
i < IDGeneratorFactory.ID_GENERATOR_METHODS.length;
i++)
{
database.addIdGenerator(
IDGeneratorFactory.ID_GENERATOR_METHODS[i],
IDGeneratorFactory.create(db, handle));
}
}
}
}
catch (InstantiationException e)
{
log.error("Error creating a database adapter instance", e);
throw new TorqueException(e);
}
catch (TorqueException e)
{
log.error("Error reading configuration seeking database "
+ "adapters", e);
throw new TorqueException(e);
}
// check that at least the default database has got an adapter.
Database defaultDatabase
= (Database) databases.get(Torque.getDefaultDB());
if (defaultDatabase == null
|| defaultDatabase.getAdapter() == null)
{
String error = "Invalid configuration : "
+ "No adapter definition found for default DB "
+ "An adapter must be defined under "
+ Torque.TORQUE_KEY
+ "."
+ Torque.DATABASE_KEY
+ "."
+ Torque.getDefaultDB()
+ "."
+ DB.ADAPTER_KEY;
log.error(error);
throw new TorqueException(error);
}
}
/**
* Reads the settings for the DataSourceFactories from the configuration
* and creates and/or cinfigures the DataSourceFactories for the databases.
* If no DataSorceFactory is assigned to the database with the name
* <code>DEFAULT_NAME</code>, a reference to the DataSourceFactory
* of the default daztabase is made from the database with the name
* <code>DEFAULT_NAME</code>.
*
* @param conf the Configuration representing the properties file
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
private void initDataSourceFactories(Configuration conf)
throws TorqueException
{
log.debug("initDataSourceFactories(" + conf + ")");
Configuration c = conf.subset(DataSourceFactory.DSFACTORY_KEY);
if (c == null || c.isEmpty())
{
String error = "Invalid configuration: "
+ "No keys starting with "
+ Torque.TORQUE_KEY
+ "."
+ DataSourceFactory.DSFACTORY_KEY
+ " found in configuration";
log.error(error);
throw new TorqueException(error);
}
try
{
for (Iterator it = c.getKeys(); it.hasNext();)
{
String key = (String) it.next();
if (key.endsWith(DataSourceFactory.FACTORY_KEY))
{
String classname = c.getString(key);
String handle = key.substring(0, key.indexOf('.'));
log.debug("handle: " + handle
+ " DataSourceFactory: " + classname);
Class dsfClass = Class.forName(classname);
DataSourceFactory dsf =
(DataSourceFactory) dsfClass.newInstance();
dsf.initialize(c.subset(handle));
Database database = getOrCreateDatabase(handle);
database.setDataSourceFactory(dsf);
}
}
}
catch (RuntimeException e)
{
log.error("Runtime Error reading adapter configuration", e);
throw new TorqueRuntimeException(e);
}
catch (Exception e)
{
log.error("Error reading adapter configuration", e);
throw new TorqueException(e);
}
Database defaultDatabase
= (Database) databases.get(defaultDBName);
if (defaultDatabase == null
|| defaultDatabase.getDataSourceFactory() == null)
{
String error = "Invalid configuration : "
+ "No DataSourceFactory definition for default DB found. "
+ "A DataSourceFactory must be defined under the key"
+ Torque.TORQUE_KEY
+ "."
+ DataSourceFactory.DSFACTORY_KEY
+ "."
+ defaultDBName
+ "."
+ DataSourceFactory.FACTORY_KEY;
log.error(error);
throw new TorqueException(error);
}
// As there might be a default database configured
// to map "default" onto an existing datasource, we
// must check, whether there _is_ really an entry for
// the "default" in the dsFactoryMap or not. If it is
// not, then add a dummy entry for the "default"
//
// Without this, you can't actually access the "default"
// data-source, even if you have an entry like
//
// database.default = bookstore
//
// in your Torque.properties
//
{
Database databaseInfoForKeyDefault
= getOrCreateDatabase(DEFAULT_NAME);
if ((!defaultDBName.equals(DEFAULT_NAME))
&& databaseInfoForKeyDefault.getDataSourceFactory() == null)
{
log.debug("Adding the DatasourceFactory from database "
+ defaultDBName
+ " onto database " + DEFAULT_NAME);
databaseInfoForKeyDefault.setDataSourceFactory(
defaultDatabase.getDataSourceFactory());
this.defaultDsfIsReference = true;
}
}
}
/**
* Initialization of Torque with a properties file.
*
* @param configFile The absolute path to the configuration file.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public void init(String configFile)
throws TorqueException
{
log.debug("init(" + configFile + ")");
try
{
Configuration configuration
= new PropertiesConfiguration(configFile);
log.debug("Config Object is " + configuration);
init(configuration);
}
catch (ConfigurationException e)
{
throw new TorqueException(e);
}
}
/**
* Initialization of Torque with a Configuration object.
*
* @param conf The Torque configuration.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public synchronized void init(Configuration conf)
throws TorqueException
{
log.debug("init(" + conf + ")");
setConfiguration(conf);
initialize();
}
/**
* Creates a mapping between classes and their manager classes.
*
* The mapping is built according to settings present in
* properties file. The entries should have the
* following form:
*
* <pre>
* torque.managed_class.com.mycompany.Myclass.manager= \
* com.mycompany.MyManagerImpl
* services.managed_class.com.mycompany.Myotherclass.manager= \
* com.mycompany.MyOtherManagerImpl
* </pre>
*
* <br>
*
* Generic ServiceBroker provides no Services.
*
* @param conf the Configuration representing the properties file
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
protected void initManagerMappings(Configuration conf)
throws TorqueException
{
int pref = Torque.MANAGER_PREFIX.length();
int suff = Torque.MANAGER_SUFFIX.length();
for (Iterator it = conf.getKeys(); it.hasNext();)
{
String key = (String) it.next();
if (key.startsWith(Torque.MANAGER_PREFIX)
&& key.endsWith(Torque.MANAGER_SUFFIX))
{
String managedClassKey = key.substring(pref,
key.length() - suff);
if (!managers.containsKey(managedClassKey))
{
String managerClass = conf.getString(key);
log.info("Added Manager for Class: " + managedClassKey
+ " -> " + managerClass);
try
{
initManager(managedClassKey, managerClass);
}
catch (TorqueException e)
{
// the exception thrown here seems to disappear.
// At least when initialized by Turbine, should find
// out why, but for now make sure it is noticed.
log.error("", e);
e.printStackTrace();
throw e;
}
}
}
}
}
/**
* Initialize a manager
*
* @param name name of the manager
* @param className name of the manager class
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
private synchronized void initManager(String name, String className)
throws TorqueException
{
AbstractBaseManager manager = (AbstractBaseManager) managers.get(name);
if (manager == null)
{
if (className != null && className.length() != 0)
{
try
{
manager = (AbstractBaseManager)
Class.forName(className).newInstance();
managers.put(name, manager);
}
catch (Exception e)
{
throw new TorqueException("Could not instantiate "
+ "manager associated with class: "
+ name, e);
}
}
}
}
/**
* Determine whether Torque has already been initialized.
*
* @return true if Torque is already initialized
*/
public boolean isInit()
{
return isInit;
}
/**
* Sets the configuration for Torque and all dependencies.
* The prefix <code>TORQUE_KEY</code> needs to be removed from the
* configuration keys for the provided configuration.
*
* @param conf the Configuration.
*/
public void setConfiguration(Configuration conf)
{
log.debug("setConfiguration(" + conf + ")");
this.conf = conf;
}
/**
* Get the configuration for this component.
*
* @return the Configuration
*/
public Configuration getConfiguration()
{
log.debug("getConfiguration() = " + conf);
return conf;
}
/**
* This method returns a Manager for the given name.
*
* @param name name of the manager
* @return a Manager
*/
public AbstractBaseManager getManager(String name)
{
AbstractBaseManager m = (AbstractBaseManager) managers.get(name);
if (m == null)
{
log.error("No configured manager for key " + name + ".");
}
return m;
}
/**
* This methods returns either the Manager from the configuration file,
* or the default one provided by the generated code.
*
* @param name name of the manager
* @param defaultClassName the class to use if name has not been configured
* @return a Manager
*/
public AbstractBaseManager getManager(String name,
String defaultClassName)
{
AbstractBaseManager m = (AbstractBaseManager) managers.get(name);
if (m == null)
{
log.debug("Added late Manager mapping for Class: "
+ name + " -> " + defaultClassName);
try
{
initManager(name, defaultClassName);
}
catch (TorqueException e)
{
log.error(e.getMessage(), e);
}
// Try again now that the default manager should be in the map
m = (AbstractBaseManager) managers.get(name);
}
return m;
}
/**
* Shuts down the service.
*
* This method halts the IDBroker's daemon thread in all of
* the DatabaseMap's. It also closes all SharedPoolDataSourceFactories
* and PerUserPoolDataSourceFactories initialized by Torque.
* @exception TorqueException if a DataSourceFactory could not be closed
* cleanly. Only the first exception is rethrown, any following
* exceptions are logged but ignored.
*/
public synchronized void shutdown()
throws TorqueException
{
// stop the idbrokers
synchronized (databases)
{
for (Iterator it = databases.values().iterator(); it.hasNext();)
{
Database database = (Database) it.next();
IDBroker idBroker = database.getIDBroker();
if (idBroker != null)
{
idBroker.stop();
}
}
}
// shut down the data source factories
TorqueException exception = null;
synchronized (databases)
{
for (Iterator it = databases.keySet().iterator(); it.hasNext();)
{
Object databaseKey = it.next();
Database database
= (Database) databases.get(databaseKey);
if (DEFAULT_NAME.equals(databaseKey) && defaultDsfIsReference)
{
// the DataSourceFactory of the database with the name
// DEFAULT_NAME is just a reference to aynother entry.
// Do not close because this leads to closing
// the same DataSourceFactory twice.
database.setDataSourceFactory(null);
break;
}
try
{
DataSourceFactory dataSourceFactory
= database.getDataSourceFactory();
if (dataSourceFactory != null)
{
dataSourceFactory.close();
database.setDataSourceFactory(null);
}
}
catch (TorqueException e)
{
log.error("Error while closing the DataSourceFactory "
+ databaseKey,
e);
if (exception == null)
{
exception = e;
}
}
}
}
if (exception != null)
{
throw exception;
}
resetConfiguration();
}
/**
* Resets some internal configuration variables to
* their defaults.
*/
private void resetConfiguration()
{
mapBuilderCache = Collections.synchronizedMap(new HashMap());
managers = new HashMap();
isInit = false;
}
/**
* Returns the default database map information.
*
* @return A DatabaseMap.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public DatabaseMap getDatabaseMap()
throws TorqueException
{
return getDatabaseMap(getDefaultDB());
}
/**
* Returns the database map information. Name relates to the name
* of the connection pool to associate with the map.
*
* @param name The name of the database corresponding to the
* <code>DatabaseMap</code> to retrieve.
* @return The named <code>DatabaseMap</code>.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public DatabaseMap getDatabaseMap(String name)
throws TorqueException
{
if (name == null)
{
throw new TorqueException ("DatabaseMap name was null!");
}
Database database = getOrCreateDatabase(name);
return database.getDatabaseMap();
}
/**
* Get the registered MapBuilders
*
* @return the MapBuilder cache
*
*/
public Map getMapBuilders()
{
return mapBuilderCache;
}
/**
* Register a MapBuilder
*
* @param className the MapBuilder
*/
public void registerMapBuilder(String className)
{
mapBuilderCache.put(className, null);
}
/**
* Register a MapBuilder
*
* @param builder the instance of the MapBuilder
*
*/
public void registerMapBuilder(MapBuilder builder)
{
mapBuilderCache.put(builder.getClass().getName(), builder);
}
/**
* Get a MapBuilder
*
* @param className of the MapBuilder
* @return A MapBuilder, not null
* @throws TorqueException if the Map Builder cannot be instantiated
*
*/
public MapBuilder getMapBuilder(String className)
throws TorqueException
{
try
{
MapBuilder mb = (MapBuilder)mapBuilderCache.get(className);
if (mb == null)
{
mb = (MapBuilder) Class.forName(className).newInstance();
// Cache the MapBuilder before it is built.
mapBuilderCache.put(className, mb);
}
if (mb.isBuilt())
{
return mb;
}
try
{
mb.doBuild();
}
catch (Exception e)
{
// remove the MapBuilder from the cache if it can't be built correctly
mapBuilderCache.remove(className);
throw e;
}
return mb;
}
catch (Exception e)
{
log.error("getMapBuilder failed trying to instantiate: "
+ className, e);
throw new TorqueException(e);
}
}
/**
* This method returns a Connection from the default pool.
*
* @return The requested connection, never null.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public Connection getConnection()
throws TorqueException
{
return getConnection(getDefaultDB());
}
/**
* Returns a database connection to the database with the key
* <code>name</code>.
* @param name The database name.
* @return a database connection, never null.
* @throws TorqueException If no DataSourceFactory is configured for the
* named database, the connection information is wrong, or the
* connection cannot be returned for any other reason.
*/
public Connection getConnection(String name)
throws TorqueException
{
if (!Torque.isInit())
{
throw new TorqueException("Torque is not initialized");
}
try
{
return getDatabase(name)
.getDataSourceFactory()
.getDataSource()
.getConnection();
}
catch (SQLException se)
{
throw new TorqueException(se);
}
}
/**
* Returns the DataSourceFactory for the database with the name
* <code>name</code>.
*
* @param name The name of the database to get the DSF for.
* @return A DataSourceFactory object, never null.
* @throws TorqueException if Torque is not initiliaized, or
* no DatasourceFactory is configured for the given name.
*/
public DataSourceFactory getDataSourceFactory(String name)
throws TorqueException
{
Database database = getDatabase(name);
DataSourceFactory dsf = null;
if (database != null)
{
dsf = database.getDataSourceFactory();
}
if (dsf == null)
{
throw new TorqueException(
"There was no DataSourceFactory "
+ "configured for the connection " + name);
}
return dsf;
}
/**
* This method returns a Connection using the given parameters.
* You should only use this method if you need user based access to the
* database!
*
* @param name The database name.
* @param username The name of the database user.
* @param password The password of the database user.
* @return A Connection.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public Connection getConnection(String name, String username,
String password)
throws TorqueException
{
if (!Torque.isInit())
{
throw new TorqueException("Torque is not initialized");
}
try
{
return getDataSourceFactory(name)
.getDataSource().getConnection(username, password);
}
catch (SQLException se)
{
throw new TorqueException(se);
}
}
/**
* Returns the database adapter for a specific database.
*
* @param name the name of the database to get the adapter for.
* @return The corresponding database adapter, or null if no database
* adapter is defined for the given database.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public DB getDB(String name) throws TorqueException
{
Database database = getDatabase(name);
if (database == null)
{
return null;
}
return database.getAdapter();
}
///////////////////////////////////////////////////////////////////////////
/**
* Returns the name of the default database.
*
* @return name of the default DB, or null if Torque is not initialized yet
*/
public String getDefaultDB()
{
return defaultDBName;
}
/**
* Closes a connection.
*
* @param con A Connection to close.
*/
public void closeConnection(Connection con)
{
if (con != null)
{
try
{
con.close();
}
catch (SQLException e)
{
log.error("Error occured while closing connection.", e);
}
}
}
/**
* Sets the current schema for a database connection
*
* @param name The database name.
* @param schema The current schema name.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public void setSchema(String name, String schema)
throws TorqueException
{
getOrCreateDatabase(name).setSchema(schema);
}
/**
* This method returns the current schema for a database connection
*
* @param name The database name.
* @return The current schema name. Null means, no schema has been set.
* @throws TorqueException Any exceptions caught during processing will be
* rethrown wrapped into a TorqueException.
*/
public String getSchema(String name)
throws TorqueException
{
Database database = getDatabase(name);
if (database == null)
{
return null;
}
return database.getSchema();
}
/**
* Returns the database for the key <code>databaseName</code>.
*
* @param databaseName the key to get the database for.
* @return the database for the specified key, or null if the database
* does not exist.
* @throws TorqueException if Torque is not yet initialized.
*/
public Database getDatabase(String databaseName) throws TorqueException
{
if (!isInit())
{
throw new TorqueException("Torque is not initialized.");
}
return (Database) databases.get(databaseName);
}
/**
* Returns a Map containing all Databases registered to Torque.
* The key of the Map is the name of the database, and the value is the
* database instance. <br/>
* Note that in the very special case where a new database which
* is not configured in Torque's configuration gets known to Torque
* at a later time, the returned map may change, and there is no way to
* protect you against this.
*
* @return a Map containing all Databases known to Torque, never null.
* @throws TorqueException if Torque is not yet initialized.
*/
public Map getDatabases() throws TorqueException
{
if (!isInit())
{
throw new TorqueException("Torque is not initialized.");
}
return Collections.unmodifiableMap(databases);
}
/**
* Returns the database for the key <code>databaseName</code>.
* If no database is associated to the specified key,
* a new database is created, mapped to the specified key, and returned.
*
* @param databaseName the key to get the database for.
* @return the database associated with specified key, or the newly created
* database, never null.
*/
public Database getOrCreateDatabase(String databaseName)
{
synchronized (databases)
{
Database result = (Database) databases.get(databaseName);
if (result == null)
{
result = new Database(databaseName);
databases.put(databaseName, result);
}
return result;
}
}
}