org.apache.tapestry
Interface ComponentResourcesCommon

All Superinterfaces:

Locatable

All Known Subinterfaces:

ComponentPageElement, ComponentResources, InternalComponentResources

All Known Implementing Classes:

ComponentPageElementImpl, InternalComponentResourcesImpl

public interface ComponentResourcesCommon
extends Locatable

Operations shared by the public ComponentResources interface and ComponentPageElement interface (on the internal side).

Method Summary

Block	findBlock(String blockId) As with getBlock(String), but returns null if the block is not found.
Block	getBlock(String blockId) Returns a block from the component's template, referenced by its id.
String	getCompleteId() Returns a string consisting of the logical name of the containing page, and the nested id of this component, separated by a colon.
String	getElementName(String defaultElementName) Returns the name of element that represents the component in its template, or the provided default element name if the element was a component type (in the Tapestry namespace).
String	getId() Returns the id of the component.
Locale	getLocale() Returns the locale for the page containing this component.
org.slf4j.Logger	getLogger() Returns the log instance associated with the component (which is based on the component or mixin's class name).
String	getNestedId() Return a string consisting the concatinated ids of all containing components, separated by periods.
String	getPageName() Returns the logical name of the page containing this component.
boolean	isRendering() Returns true if the component is currently rendering, false otherwise.
boolean	triggerContextEvent(String eventType, EventContext context, ComponentEventCallback callback) Triggers a component event.
boolean	triggerEvent(String eventType, Object[] contextValues, ComponentEventCallback callback) A convienience for invoking triggerContextEvent(String, EventContext , ComponentEventCallback).

Methods inherited from interface org.apache.tapestry.ioc.Locatable

getLocation

Method Detail

getId

String getId()

Returns the id of the component. The id will be unique within the component's immediate container. For a page's root component, the value null is returned.

getNestedId

String getNestedId()

Return a string consisting the concatinated ids of all containing components, separated by periods. In addition, nested ids are always all lower case. I.e., "foo.bar.baz". Returns null for the root component of a page.

getCompleteId

String getCompleteId()

Returns a string consisting of the logical name of the containing page, and the nested id of this component, separated by a colon. I.e., "mypage:foo.bar.baz". For a page, returns just the page's logical name.

This value is often used to obtain an equivalent component instance in a later request.

See Also:

ComponentSource.getComponent(String)

triggerEvent

boolean triggerEvent(String eventType,
                     Object[] contextValues,
                     ComponentEventCallback callback)

A convienience for invoking triggerContextEvent(String, EventContext , ComponentEventCallback). Wraps the context values into an EventContext.

Parameters:

eventType - event type (as determined from the request, or otherwise by design)

context - Values that may be provided to the event handler method as method parameters, or null if no context values are available

callback - the handler to be informed of the result, or null if the event is a notification that does not support return values from event handler methods (the value true is allowed even if the handler is null).

Returns:

true if any event handler was invoked (even if no event handler method returns a non-null value)

Throws:

ComponentEventException - if an event handler method throws a checked or unchecked exception

See Also:

OnEventWorker, OnEvent

triggerContextEvent

boolean triggerContextEvent(String eventType,
                            EventContext context,
                            ComponentEventCallback callback)

Triggers a component event. A search for an event handling method will occur, first in the component, then its container, and so on. When a matching event handler method is located, it is invoked. If the method returns a value, the value is passed to the callback (if callback is null, then it is an error for a method to return a non-null value).

Resolution of event type to event handler methods is case insensitive.

Parameters:

eventType - event type (as determined from the request, or otherwise by design)

context - the context (as extracted from the request, or provided by the triggering component); these values may be provided to event handler methods via their parameters (may not be null)

callback - the handler to be informed of the result, or null if the event is a notification that does not support return values from event handler methods (the value true is allowed even if the handler is null).

Returns:

true if any event handler was invoked (even if no event handler method returns a non-null value)

Throws:

ComponentEventException - if an event handler method throws a checked or unchecked exception

See Also:

OnEventWorker, OnEvent

isRendering

boolean isRendering()

Returns true if the component is currently rendering, false otherwise. This is most often used to determine if parameter values should be cached.

getLogger

org.slf4j.Logger getLogger()

Returns the log instance associated with the component (which is based on the component or mixin's class name).

See Also:

ComponentModel.getLogger()

getLocale

Locale getLocale()

Returns the locale for the page containing this component.

getElementName

String getElementName(String defaultElementName)

Returns the name of element that represents the component in its template, or the provided default element name if the element was a component type (in the Tapestry namespace).

Parameters:

defaultElementName - element name to return if the element name is not known (may be null)

Returns:

the element name

getBlock

Block getBlock(String blockId)

Returns a block from the component's template, referenced by its id.

Parameters:

blockId - the id of the block (case insensitive)

Returns:

the identified Block

Throws:

BlockNotFoundException - if no block with the given id exists

See Also:

findBlock(String)

findBlock

Block findBlock(String blockId)

As with getBlock(String), but returns null if the block is not found.

Parameters:

blockId - the id of the block (case insensitive)

Returns:

the block, or null

getPageName

String getPageName()

Returns the logical name of the page containing this component. This is the short name (it often appears in URLs)

Returns:

the logical name of the page which contains this component