org.apache.avalon.fortress.util
Class ContextManager

java.lang.Object
  org.apache.avalon.fortress.util.ContextManager

All Implemented Interfaces:

ContainerConstants, ContainerManagerConstants, ContextManagerConstants, Disposable, Initializable

public class ContextManager

extends java.lang.Object

implements ContextManagerConstants, Initializable, Disposable

You can get two different contexts from the ContextManager: the container context (m_childContext) and the container manager context (m_containerManagerContext)

You can get two different contexts from the ContextManager: the child context and the impl manager context. The former contains all managers, such as the pool manager etc. necessary for a child impl to create additional child containers. The impl manager context contains all of the child context, but also initialization parameters for the impl, such as a Configuration object, a ComponentLocator, etc., that the impl wants, but does not want to pass on to its children.

The container manager context is used to provide the container manager with all the data needed to initialize the container.

The container context is passed directly to the container.

The ContextManager will sometimes create new components, such as a service manager, a pool manager, etc. It will manage these components and dispose of them properly when it itself is disposed .

Since:

4.1

Version:

CVS $Revision: 1.55 $ $Date: 2004/04/05 12:05:38 $

Author:

Avalon Development Team

Field Summary

protected static Configuration	EMPTY_CONFIG
protected DefaultContext	m_childContext The context of the new impl.
protected DefaultContext	m_containerManagerContext Container manager's context.
protected SourceResolver	m_defaultSourceResolver Source resolver used to read-in the configurations.
protected InstrumentManager	m_instrumentManager The InstrumentManager to be used by the container.
protected Logger	m_logger
protected LoggerManager	m_loggerManager The logger manager in use.
protected MetaInfoManager	m_metaInfoManager The MetaInfoManager to be used by the container.
protected org.d_haven.mpool.PoolManager	m_poolManager The PoolManager to be used by the container.
protected Logger	m_primordialLogger
protected Context	m_rootContext The root context.
protected org.d_haven.event.Sink	m_sink The Sink in use.
protected org.d_haven.event.command.ThreadManager	m_threadManager The ThreadManager to be used by the container.

Fields inherited from interface org.apache.avalon.fortress.util.ContextManagerConstants

CONFIGURATION_URI, INSTRUMENT_MANAGER_CONFIGURATION, INSTRUMENT_MANAGER_CONFIGURATION_URI, LOG_CATEGORY, LOGGER_MANAGER_CONFIGURATION, LOGGER_MANAGER_CONFIGURATION_URI, ROLE_MANAGER_CLASS, ROLE_MANAGER_CONFIGURATION, ROLE_MANAGER_CONFIGURATION_URI

Fields inherited from interface org.apache.avalon.fortress.ContainerManagerConstants

COMMAND_FAILURE_HANDLER_CLASS, CONFIGURATION, CONTAINER_CLASS, LOGGER, PARAMETERS, SERVICE_MANAGER

Fields inherited from interface org.apache.avalon.fortress.ContainerConstants

CONTEXT_DIRECTORY, THREAD_TIMEOUT, THREADS_CPU, WORK_DIRECTORY

Constructor Summary

ContextManager(Context rootContext, Logger logger)
Create a new ContextManager.

Method Summary

protected void	assumeOwnership(java.lang.Object object) Method to assume ownership of one of the managers the ContextManager created.
protected void	copyEntry(java.lang.String key) Copies the specified entry from the rootContext to the containerManagerContext.
void	dispose() Disposes all items that this ContextManager has created.
void	disposeOwned() Disposes all items ContextManager has assumed ownership over
protected boolean	entryPresent(Context context, java.lang.String key) Checks if a specified entry in context has been supplied by the invoker.
protected java.lang.Object	get(Context context, java.lang.String key, java.lang.Object defaultValue) Convenience method to obtain a value, or defer to a default if it does not exist.
Context	getChildContext() Finalizes and returns the context.
protected Configuration	getConfiguration(java.lang.String configKey, java.lang.String uriKey) Get a configuration based on a config and URI key.
Context	getContainerManagerContext() Finalizes and returns the context.
protected Logger	getLogger() Get a reference the Logger.
void	initialize() Initialize the ContextManager.
protected void	initializeCommandSink() Set up the CommandSink to enable asynchronous management.
protected void	initializeConfiguration() Load the configuration file that the Container will need to operate.
protected void	initializeContext() Initialize the context that will be passed into the impl.
protected void	initializeDefaultSourceResolver() Initialize the default source resolver
protected void	initializeInstrumentManager() Will set up an InstrumentManager if none is supplied.
protected void	initializeLoggerManager() Will set up a LogKitLoggerManager if none is supplied.
protected void	initializeMetaInfoManager()
protected void	initializePoolManager() Set up the Pool Manager for the managed pool.
protected void	initializeServiceManager() Get a reference to the initial ComponentLocator used by the ContainerManager to hold the Components used for parsing the config files and setting up the environment.
protected void	initializeThreadManager()
protected RoleManager	obtainRoleManager() Set up a RoleManager for the Container if configuration for it has been supplied.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_CONFIG

protected static final Configuration EMPTY_CONFIG

m_rootContext

protected final Context m_rootContext

The root context.

m_childContext

protected final DefaultContext m_childContext

The context of the new impl. This context has the rootContext as its parent. Put everything here that you want the new impl to have in its own context.

m_containerManagerContext

protected final DefaultContext m_containerManagerContext

Container manager's context. This context has the child context as parent. Put things here that you want the impl manager to see, but do not wish to expose to the impl.

m_logger

protected Logger m_logger

m_primordialLogger

protected final Logger m_primordialLogger

m_defaultSourceResolver

protected SourceResolver m_defaultSourceResolver

Source resolver used to read-in the configurations. and provided as a default source resolver if the user has not supplied a ServiceManager.

m_loggerManager

protected LoggerManager m_loggerManager

The logger manager in use. Either supplied via rootContext, or created locally.

m_sink

protected org.d_haven.event.Sink m_sink

The Sink in use. Either supplied via rootContext or created locally.

m_metaInfoManager

protected MetaInfoManager m_metaInfoManager

The MetaInfoManager to be used by the container. Either supplied via rootContext or created locally.

m_poolManager

protected org.d_haven.mpool.PoolManager m_poolManager

The PoolManager to be used by the container. Either supplied via rootContext or created locally.

m_threadManager

protected org.d_haven.event.command.ThreadManager m_threadManager

The ThreadManager to be used by the container. Either supplied via rootContext or created locally.

m_instrumentManager

protected InstrumentManager m_instrumentManager

The InstrumentManager to be used by the container. Either supplied via rootContext or created locally.

Constructor Detail

ContextManager

public ContextManager(Context rootContext,
                      Logger logger)

Create a new ContextManager.

Parameters:

rootContext - the default values.

logger - logger to use when creating new components.

Method Detail

assumeOwnership

protected void assumeOwnership(java.lang.Object object)

Method to assume ownership of one of the managers the ContextManager created. Ownership means that the ContextManager is responsible for destroying the manager when the ContextManager is destroyed.

Parameters:

object - The object being claimed

Throws:

java.lang.IllegalArgumentException - if the object is null.

initialize

public void initialize()
                throws java.lang.Exception

Initialize the ContextManager. This will cause the ContextManager to create any managers it needs.

Specified by:

initialize in interface Initializable

Throws:

java.lang.Exception - if there is a problem at any point in the initialization.

initializeConfiguration

protected void initializeConfiguration()

Load the configuration file that the Container will need to operate.

initializeContext

protected void initializeContext()
                          throws java.lang.Exception

Initialize the context that will be passed into the impl.

Throws:

java.lang.Exception - if any of the parameters cannot be copied properly.

copyEntry

protected void copyEntry(java.lang.String key)
                  throws ContextException

Copies the specified entry from the rootContext to the containerManagerContext.

Throws:

ContextException - if the parameter does not exist

entryPresent

protected boolean entryPresent(Context context,
                               java.lang.String key)

Checks if a specified entry in context has been supplied by the invoker.

Parameters:

context - The context to check

key - The key name to check

dispose

public void dispose()

Disposes all items that this ContextManager has created.

Specified by:

dispose in interface Disposable

disposeOwned

public void disposeOwned()

Disposes all items ContextManager has assumed ownership over

get

protected java.lang.Object get(Context context,
                               java.lang.String key,
                               java.lang.Object defaultValue)

Convenience method to obtain a value, or defer to a default if it does not exist.

Parameters:

context - The context object we intend to get a value from.

key - The key we want to use to get the value.

defaultValue - The default value we return if the key does not exist.

initializeCommandSink

protected void initializeCommandSink()
                              throws java.lang.Exception

Set up the CommandSink to enable asynchronous management.

Throws:

java.lang.Exception - if the CommandSink could not be created.

initializePoolManager

protected void initializePoolManager()
                              throws java.lang.Exception

Set up the Pool Manager for the managed pool.

Throws:

java.lang.Exception - if there is an error.

obtainRoleManager

protected RoleManager obtainRoleManager()
                                 throws java.lang.Exception

Set up a RoleManager for the Container if configuration for it has been supplied.

Throws:

java.lang.Exception - if there is an error.

initializeMetaInfoManager

protected void initializeMetaInfoManager()
                                  throws java.lang.Exception

Throws:

java.lang.Exception

initializeDefaultSourceResolver

protected void initializeDefaultSourceResolver()
                                        throws java.lang.Exception

Initialize the default source resolver

Throws:

java.lang.Exception - when there is an error.

initializeServiceManager

protected void initializeServiceManager()
                                 throws java.lang.Exception

Get a reference to the initial ComponentLocator used by the ContainerManager to hold the Components used for parsing the config files and setting up the environment.

Throws:

java.lang.Exception - when there is an error.

getConfiguration

protected Configuration getConfiguration(java.lang.String configKey,
                                         java.lang.String uriKey)

Get a configuration based on a config and URI key.

Parameters:

configKey - Get the Configuration object directly from the context.

uriKey - Get the uri from the context.

getContainerManagerContext

public Context getContainerManagerContext()

Finalizes and returns the context.

Returns:

a Context

getChildContext

public Context getChildContext()

Finalizes and returns the context.

Returns:

a Context

getLogger

protected Logger getLogger()

Get a reference the Logger.

Returns:

a Logger

initializeLoggerManager

protected void initializeLoggerManager()
                                throws java.lang.Exception

Will set up a LogKitLoggerManager if none is supplied. This can be overridden if you don't want a LogKitLoggerManager.

The postcondition is that childContext.get( LoggerManager.ROLE ) should return a valid logger manager.

Throws:

java.lang.Exception - if it cannot instantiate the LoggerManager

initializeThreadManager

protected void initializeThreadManager()
                                throws java.lang.Exception

Throws:

java.lang.Exception

initializeInstrumentManager

protected void initializeInstrumentManager()
                                    throws java.lang.Exception

Will set up an InstrumentManager if none is supplied. This can be overridden if you don't want an InstrumentManager

The postcondition is that childContext.get( InstrumentManager.ROLE ) should return a valid instrument manager.

Throws:

java.lang.Exception - if it cannot instantiate the InstrumentManager