org.apache.velocity.app.event

Class EventCartridge

java.lang.Object

org.apache.velocity.app.event.EventCartridge

public class EventCartridge
extends Object

Stores the event handlers. Event handlers can be assigned on a per VelocityEngine instance basis by specifying the class names in the velocity.properties file. Event handlers may also be assigned on a per-page basis by creating a new instance of EventCartridge, adding the event handlers, and then calling attachToContext. For clarity, it's recommended that one approach or the other be followed, as the second method is primarily presented for backwards compatibility.

Note that Event Handlers follow a filter pattern, with multiple event handlers allowed for each event. When the appropriate event occurs, all the appropriate event handlers are called in the sequence they were added to the Event Cartridge. See the javadocs of the specific event handler interfaces for more details.

Version:

$Id$

Author:

Will Glass-Husain , Geir Magnusson Jr. , Jose Alberto Fernandez

Field Summary

Fields

Modifier and Type	Field and Description
protected RuntimeServices	rsvc

Constructor Summary

Constructors

Constructor and Description
EventCartridge()

Method Summary

Modifier and Type	Method and Description
boolean	addEventHandler(EventHandler ev) Adds an event handler(s) to the Cartridge.
void	addIncludeEventHandler(IncludeEventHandler ev) Add an include event handler to the Cartridge.
void	addInvalidReferenceEventHandler(InvalidReferenceEventHandler ev) Add an invalid reference event handler to the Cartridge.
void	addMethodExceptionHandler(MethodExceptionEventHandler ev) Add a method exception event handler to the Cartridge.
void	addReferenceInsertionEventHandler(ReferenceInsertionEventHandler ev) Add a reference insertion event handler to the Cartridge.
boolean	attachToContext(Context context) Attached the EventCartridge to the context Final because not something one should mess with lightly :)
protected org.slf4j.Logger	getLog()
String	includeEvent(Context context, String includeResourcePath, String currentResourcePath, String directiveName) Call include event handlers
Object	invalidGetMethod(Context context, String reference, Object object, String property, Info info) Call invalid reference handlers for an invalid getter
Object	invalidMethod(Context context, String reference, Object object, String method, Info info) Call invalid reference handlers for an invalid method call
boolean	invalidSetMethod(Context context, String leftreference, String rightreference, Info info) Call invalid reference handlers for an invalid setter
Object	methodException(Context context, Class<?> claz, String method, Exception e, Info info) Call method exception event handler
Object	referenceInsert(InternalContextAdapter context, String reference, Object value) Call reference insertion handlers
boolean	removeEventHandler(EventHandler ev) Removes an event handler(s) from the Cartridge.
void	setRuntimeServices(RuntimeServices rs) runtime services setter, called during initialization

Methods inherited from class java.lang.Object

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

Field Detail

rsvc

protected RuntimeServices rsvc

Constructor Detail

EventCartridge

public EventCartridge()

Method Detail

getLog

protected org.slf4j.Logger getLog()

setRuntimeServices

public void setRuntimeServices(RuntimeServices rs)

runtime services setter, called during initialization

Parameters:

rs - runtime services

Since:

2.0

addEventHandler

public boolean addEventHandler(EventHandler ev)

Adds an event handler(s) to the Cartridge. This method will find all possible event handler interfaces supported by the passed in object.

Parameters:

ev - object implementing a valid EventHandler-derived interface

Returns:

true if a supported interface, false otherwise or if null

addReferenceInsertionEventHandler

public void addReferenceInsertionEventHandler(ReferenceInsertionEventHandler ev)

Add a reference insertion event handler to the Cartridge.

Parameters:

ev - ReferenceInsertionEventHandler

Since:

1.5

addMethodExceptionHandler

public void addMethodExceptionHandler(MethodExceptionEventHandler ev)

Add a method exception event handler to the Cartridge.

Parameters:

ev - MethodExceptionEventHandler

Since:

1.5

addIncludeEventHandler

public void addIncludeEventHandler(IncludeEventHandler ev)

Add an include event handler to the Cartridge.

Parameters:

ev - IncludeEventHandler

Since:

1.5

addInvalidReferenceEventHandler

public void addInvalidReferenceEventHandler(InvalidReferenceEventHandler ev)

Add an invalid reference event handler to the Cartridge.

Parameters:

ev - InvalidReferenceEventHandler

Since:

1.5

removeEventHandler

public boolean removeEventHandler(EventHandler ev)

Removes an event handler(s) from the Cartridge. This method will find all possible event handler interfaces supported by the passed in object and remove them.

Parameters:

ev - object impementing a valid EventHandler-derived interface

Returns:

true if event handler was previously registered, false if not found

referenceInsert

public Object referenceInsert(InternalContextAdapter context,
                              String reference,
                              Object value)

Call reference insertion handlers

Parameters:

context -

reference -

value -

Returns:

value returned by handlers

Since:

2.0

methodException

public Object methodException(Context context,
                              Class<?> claz,
                              String method,
                              Exception e,
                              Info info)

Call method exception event handler

Parameters:

context -

claz -

method -

e - exception

info - template name, line and column infos

Returns:

value returned by handler

Since:

2.0

includeEvent

public String includeEvent(Context context,
                           String includeResourcePath,
                           String currentResourcePath,
                           String directiveName)

Call include event handlers

Parameters:

context -

includeResourcePath -

currentResourcePath -

directiveName -

Returns:

include path

Since:

2.0

invalidGetMethod

public Object invalidGetMethod(Context context,
                               String reference,
                               Object object,
                               String property,
                               Info info)

Call invalid reference handlers for an invalid getter

Parameters:

context -

reference -

object -

property -

info -

Returns:

value returned by handlers

Since:

2.0

invalidSetMethod

public boolean invalidSetMethod(Context context,
                                String leftreference,
                                String rightreference,
                                Info info)

Call invalid reference handlers for an invalid setter

Parameters:

context -

leftreference -

rightreference -

info -

Returns:

whether to stop further chaining in the next cartridge

Since:

2.0

invalidMethod

public Object invalidMethod(Context context,
                            String reference,
                            Object object,
                            String method,
                            Info info)

Call invalid reference handlers for an invalid method call

Parameters:

context -

reference -

object -

method -

info -

Returns:

value returned by handlers

Since:

2.0

attachToContext

public final boolean attachToContext(Context context)

Attached the EventCartridge to the context Final because not something one should mess with lightly :)

Parameters:

context - context to attach to

Returns:

true if successful, false otherwise