org.apache.avalon.fortress.util
Class LifecycleExtensionManager

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.avalon.fortress.util.LifecycleExtensionManager

All Implemented Interfaces:

LogEnabled

public final class LifecycleExtensionManager

extends AbstractLogEnabled

LifecycleExtensionManager class. This class manages a list of extensions objects that are executed on components during the various stages of their lifecycles.

It provides methods for adding extension objects to the system, and a method for executing them on a particular component object. The current context is also passed in to the extension objects to facilitate the communication of any global values.

Extensions are stored internally in a list. This guarentees that the order in which they are executed matches the order in which they are inserted.

Version:

CVS $Revision: 1.12 $ $Date: 2004/02/28 15:16:26 $

Author:

Avalon Development Team

Field Summary

protected static int	ACCESS
protected static int	CREATE
protected static int	DESTROY
protected static int	RELEASE
static java.lang.String	ROLE

Constructor Summary

LifecycleExtensionManager()

Method Summary

int	accessorExtensionsCount() Find out the total number of accessor extensions registered with this manager
java.util.Iterator	accessorExtensionsIterator() Obtain an iterator.
void	addAccessorExtension(Accessor extension) Adds an accessor extension to the manager
void	addCreatorExtension(Creator extension) Adds a creator extension to the manager
protected void	checkWriteable() Utility method to check if LifecycleExtensionsManager is writeable and if not throw exception.
void	clearAccessorExtensions() Clears all accessor extensions registered with this manager
void	clearCreatorExtensions() Clears all creator extensions registered with this manager
int	creatorExtensionsCount() Find out the total number of creator extensions registered with this manager
java.util.Iterator	creatorExtensionsIterator() Obtain an iterator.
void	executeAccessExtensions(java.lang.Object component, Context context) executeAccessExtensions method, executes all access level extensions on the given component.
void	executeCreationExtensions(java.lang.Object component, Context context) executeCreationExtensions method, executes all creation level extensions on the given component.
void	executeDestructionExtensions(java.lang.Object component, Context context) executeDestructionExtensions method, executes all destruction level extensions on the given component.
protected void	executeExtensions(java.lang.Object[] extensions, java.lang.Object component, Context context, int type) executeExtensions method, executes a given array of lifecycle interfaces on a given component.
void	executeReleaseExtensions(java.lang.Object component, Context context) executeReleaseExtensions method, executes all release level extensions on the given component.
Accessor	getAccessorExtension(int index) Obtain the particular accessor extension at the given index
Creator	getCreatorExtension(int index) Obtain the particular creator extension at the given index
void	insertAccessorExtension(int position, Accessor extension) Inserts an accessor extension at a given index in the manager
void	insertCreatorExtension(int position, Creator extension) Inserts a creator extension at a given index in the manager
void	makeReadOnly() Make the extension manager read only (immutable).
Accessor	removeAccessorExtension(int position) Removes a particular accessor extension from the manager
Creator	removeCreatorExtension(int position) Removes a particular creator extension from the manager
LifecycleExtensionManager	writeableCopy() Create a copy; it will be writeable even if the original was not.

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

enableLogging, getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Field Detail

ROLE

public static final java.lang.String ROLE

ACCESS

protected static final int ACCESS

See Also:

Constant Field Values

RELEASE

protected static final int RELEASE

See Also:

Constant Field Values

CREATE

protected static final int CREATE

See Also:

Constant Field Values

DESTROY

protected static final int DESTROY

See Also:

Constant Field Values

Constructor Detail

LifecycleExtensionManager

public LifecycleExtensionManager()

Method Detail

makeReadOnly

public void makeReadOnly()

Make the extension manager read only (immutable).

writeableCopy

public LifecycleExtensionManager writeableCopy()

Create a copy; it will be writeable even if the original was not.

executeAccessExtensions

public void executeAccessExtensions(java.lang.Object component,
                                    Context context)
                             throws java.lang.Exception

executeAccessExtensions method, executes all access level extensions on the given component.

Parameters:

component - a Component instance

context - a Context instance

Throws:

java.lang.Exception - if an error occurs

executeReleaseExtensions

public void executeReleaseExtensions(java.lang.Object component,
                                     Context context)
                              throws java.lang.Exception

executeReleaseExtensions method, executes all release level extensions on the given component.

Parameters:

component - a Component instance

context - a Context instance

Throws:

java.lang.Exception - if an error occurs

executeCreationExtensions

public void executeCreationExtensions(java.lang.Object component,
                                      Context context)
                               throws java.lang.Exception

executeCreationExtensions method, executes all creation level extensions on the given component.

Parameters:

component - a Component instance

context - a Context instance

Throws:

java.lang.Exception - if an error occurs

executeDestructionExtensions

public void executeDestructionExtensions(java.lang.Object component,
                                         Context context)
                                  throws java.lang.Exception

executeDestructionExtensions method, executes all destruction level extensions on the given component.

Parameters:

component - a Component instance

context - a Context instance

Throws:

java.lang.Exception - if an error occurs

addAccessorExtension

public void addAccessorExtension(Accessor extension)

Adds an accessor extension to the manager

Parameters:

extension - a Accessor instance

addCreatorExtension

public void addCreatorExtension(Creator extension)

Adds a creator extension to the manager

Parameters:

extension - a Creator instance

insertAccessorExtension

public void insertAccessorExtension(int position,
                                    Accessor extension)

Inserts an accessor extension at a given index in the manager

Parameters:

position - an int index value

extension - a Accessor instance

insertCreatorExtension

public void insertCreatorExtension(int position,
                                   Creator extension)

Inserts a creator extension at a given index in the manager

Parameters:

position - an int index value

extension - a Creator instance

removeAccessorExtension

public Accessor removeAccessorExtension(int position)

Removes a particular accessor extension from the manager

Parameters:

position - an int index value

Returns:

a Accessor instance

removeCreatorExtension

public Creator removeCreatorExtension(int position)

Removes a particular creator extension from the manager

Parameters:

position - an int index value

Returns:

a Creator instance

accessorExtensionsIterator

public java.util.Iterator accessorExtensionsIterator()

Obtain an iterator.

Returns:

an Iterator instance

creatorExtensionsIterator

public java.util.Iterator creatorExtensionsIterator()

Obtain an iterator.

Returns:

an Iterator instance

accessorExtensionsCount

public int accessorExtensionsCount()

Find out the total number of accessor extensions registered with this manager

Returns:

an int value

creatorExtensionsCount

public int creatorExtensionsCount()

Find out the total number of creator extensions registered with this manager

Returns:

an int value

getAccessorExtension

public Accessor getAccessorExtension(int index)

Obtain the particular accessor extension at the given index

Parameters:

index - an int index value

Returns:

a Accessor instance

getCreatorExtension

public Creator getCreatorExtension(int index)

Obtain the particular creator extension at the given index

Parameters:

index - an int index value

Returns:

a Creator instance

clearAccessorExtensions

public void clearAccessorExtensions()

Clears all accessor extensions registered with this manager

clearCreatorExtensions

public void clearCreatorExtensions()

Clears all creator extensions registered with this manager

executeExtensions

protected void executeExtensions(java.lang.Object[] extensions,
                                 java.lang.Object component,
                                 Context context,
                                 int type)
                          throws java.lang.Exception

executeExtensions method, executes a given array of lifecycle interfaces on a given component.

Parameters:

component - a Component instance

context - a Context instance

type - a constant, referencing which phase the extensions array adheres to

Throws:

java.lang.Exception - if an error occurs

checkWriteable

protected final void checkWriteable()
                             throws java.lang.IllegalStateException

Utility method to check if LifecycleExtensionsManager is writeable and if not throw exception.

Throws:

java.lang.IllegalStateException - if context is read only