net.sf.basedb.util.extensions
Class ExtensionsInvoker<A extends Action>

java.lang.Object
  net.sf.basedb.util.extensions.ExtensionsInvoker<A>

public class ExtensionsInvoker<A extends Action>
extends Object

Object of this class handles a single invokation of the extensions for one or several extension points. Call Registry.useExtensions(ClientContext, ExtensionsFilter, String...) to create an invoker object. With this object you can iterate() over all actions created by the extensions, or use one of the render methods to render all actions automatically.

The renderDefault() method uses the default render objects registered with the extension points and/or extensions (see ExtensionPoint.getRendererFactory() and Extension.getRendererFactory()). Since the registration of rendering factories are optional, the renderDefault() method only works with extensions that have done so. If an action can't be associated with a renderer, an exception is thrown.

If there is no default rendering factory or if you want to override the default renderer, you can use the render(Renderer) method. This will force the use of the specified renderer for all extensions, ignoring all renderers set by extension points or extensions.

Version:

2.7

Author:

nicklas

Last modified

$Date:2008-03-20 12:15:25 +0100 (Thu, 20 Mar 2008) $

Field Summary

private boolean	clearErrors
private Collection<ExtensionContext<A>>	contexts

Constructor Summary

ExtensionsInvoker(Collection<ExtensionContext<A>> contexts)
Creates a new invoker object.

Method Summary

int	getNumExtensions() Get the number of enabled extensions in this invokation.
ActionIterator<A>	iterate() Create an iterator that iterates over all Action:s created by the extensions.
void	render(Renderer<A> renderer) Render all actions using a specific renderer.
void	renderDefault() Render all actions using the renderers created by the default renderer factories as specified by the registered extension points and/or extensions.
void	renderDefault(WrappingRenderer<A> wrapper) Render all actions by wrapping the default renderers by the given wrapping renderer.
void	setClearErrors(boolean clearErrors) Set a flag to indicate if existing errors should be cleared before an action is rendered.

Methods inherited from class java.lang.Object

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

Field Detail

contexts

private final Collection<ExtensionContext<A extends Action>> contexts

clearErrors

private boolean clearErrors

Constructor Detail

ExtensionsInvoker

ExtensionsInvoker(Collection<ExtensionContext<A>> contexts)

Creates a new invoker object.

Method Detail

setClearErrors

public void setClearErrors(boolean clearErrors)

Set a flag to indicate if existing errors should be cleared before an action is rendered. If this setting is not enabled (default) old errors are never cleared.

Parameters:

clearErrors - TRUE to clear old errors, FALSE to keep them

Since:

2.9

getNumExtensions

public int getNumExtensions()

Get the number of enabled extensions in this invokation. Note that this number doesn't have to correspond to the actual number of actions since an extension may choose to create 0, 1 or more actions.

Returns:

The number of enabled extensions

Since:

2.12

iterate

public ActionIterator<A> iterate()

Create an iterator that iterates over all Action:s created by the extensions. The iterator may return zero actions if none has been created.

Returns:

An iterator

renderDefault

public void renderDefault()

Render all actions using the renderers created by the default renderer factories as specified by the registered extension points and/or extensions.

See Also:

ExtensionPoint.getRendererFactory(), Extension.getRendererFactory()

renderDefault

public void renderDefault(WrappingRenderer<A> wrapper)

Render all actions by wrapping the default renderers by the given wrapping renderer.

Parameters:

wrapper - A wrapping renderer, or null to not wrap the default renderers

Since:

2.12

render

public void render(Renderer<A> renderer)

Render all actions using a specific renderer. The given renderer will be used even if an extension point has provided a renderer factory and disallowed overriding it.

See Also:

ExtensionPoint.getRendererFactory(), ExtensionPoint.allowRendererOverride()