Package org.xj3d.core.loading

Interface ScriptLoader

All Known Implementing Classes:

DefaultScriptLoader

public interface ScriptLoader

Abstract representation of a class that can be used to provide script loading and initlisation facilities to the browser core.

The loader also takes part in the event model evaluation as well. For this, it must hook into the URL change handling through the VRMLUrlListener interface and participate as part of the larger event model. Method calls are provided in this interface for other classes (eg EventModelEvaluator) to make calls to at the appropriate time in the event model. This interface does not extend the URLListener interface directly as it assumes that an implementation may take other internal arrangements. It assumes that listeners will be registered with the script nodes.

For VRML97/X3D conformant behaviour, the implied architecture of an implementation of this interface is 5 separate buckets of data:

1. Waiting to be loaded
2. In the process of being loaded
3. Load complete (or failed) and waiting for initialize() to be called
4. Load finished (or failed), nothing left to do
5. Previously loaded scripts that have had set_url called and need to shutdown the old script and start the load process for others.

Version:

$Revision: 1.2 $

Author:

Justin Couch

Method Summary

Modifier and Type	Method	Description
int	getNumberInProgress()	Get the number of items in progress of loading.
void	loadScript(VRMLScriptNodeType script)	Attempt to load the script.
void	registerScriptingEngine(ScriptEngine engine)	Register a new scripting engine with this loader.
void	setErrorReporter(org.j3d.util.ErrorReporter reporter)	Register an error reporter with the engine so that any errors generated by the loading of script code can be reported in a nice, pretty fashion.
void	setStatusListener(ScriptLoadStatusListener l)	Set the script load status listener for this loader.
void	shutdown()	Notification that the manager needs to shut down all the currently running threads.
void	unregisterScriptingEngine(ScriptEngine engine)	Unregister a the scripting engine with this loader.

Method Details

setErrorReporter

void setErrorReporter(org.j3d.util.ErrorReporter reporter)

Register an error reporter with the engine so that any errors generated by the loading of script code can be reported in a nice, pretty fashion. Setting a value of null will clear the currently set reporter. If one is already set, the new value replaces the old.

Parameters:

reporter - The instance to use or null

registerScriptingEngine

void registerScriptingEngine(ScriptEngine engine)

Register a new scripting engine with this loader. There can be only one scripting engine per content type so if the new engine supports a content type that is already registered, the new engine will replace the old one.

Parameters:

engine - The new engine instance to register

unregisterScriptingEngine

void unregisterScriptingEngine(ScriptEngine engine)

Unregister a the scripting engine with this loader. If the engine was not registered in the first place, this method is ignored.

Parameters:

engine - The engine instance to deregister

setStatusListener

void setStatusListener(ScriptLoadStatusListener l)

Set the script load status listener for this loader. A null value is used to clear the reference.

Parameters:

l - The listener instance to use or null

loadScript

void loadScript(VRMLScriptNodeType script)

Attempt to load the script. Queues the script and lets the internals deal with it.

Parameters:

script - The script instance to load

getNumberInProgress

int getNumberInProgress()

Get the number of items in progress of loading.

Returns:

The number of items queued.

shutdown

void shutdown()

Notification that the manager needs to shut down all the currently running threads. Normally called when the application is exiting, so it is not expected that the manager needs to act sanely after this method has been called.