uk.ac.kcl.cch.jb.pliny.dnd
Interface IResourceExtensionProcessor

All Known Implementing Classes:

AbstractResourceExtensionProcessor

public interface IResourceExtensionProcessor

Plugins who wish to interact with Pliny should implement this interface. See the extension point defined by the Pliny Plugin 'resourceExtensionProcessor'.

The interface makes it possible for Pliny to do several things with the the implementor:

• Drag and Drop: a plugin can choose to require that materials that are to be shared with Pliny must be imported by dropping them onto Pliny's Resource Explorer. This is done with the Image and PDF plugins, where in both cases the resource is cached, and in the case of Images, the dropped object might be a webbed page that must be harvested for suitable images. This interface makes it possible for Pliny to call code implemented here when a drop is done. Methods involved in supporting Drag and Drop are:
  • canHandleObject
  • processDrop
• Defining a Resource: when a resource is being fetched from the backing DB it can always be created as a Resource. In some cases, however, a plugin may want its resources to be setup as a class derived from Resource. Code here allows this to happen.
  • makeMyResource
  • getSource
• Displaying resource content: When a resource is displayed in a Pliny-supported viewer or editor by virtue of appearing in a LinkableObject it should be able to get the Resource Object's content from the owning plugin. This is supported here.
  • getContentFigure

Which IResourceExtensionProcessor to use is determined by the resource's ObjectType. Thus, the implementor must identify which resource type he is for by providing it through method getMyObjectType

Author:

John Bradley

See Also:

AbstractResourceExtensionProcessor which provides some useful common code to support drop processing.

Nested Class Summary

static class

IResourceExtensionProcessor.CacheElement

Method Summary

boolean	canHandleObject(Object data) tests an object that has been dropped onto an ObjectType folder within the Resource Explorer to see if this object can process it.
IResourceExtensionProcessor.CacheElement[]	getCacheElements(Resource r) provides access to cache data you want stored in the pliny archive file.
org.eclipse.draw2d.IFigure	getContentFigure(Resource resource) return an IFigure object that can be used to provide a 'content' display by Pliny.
ObjectType	getMyObjectType() provides the ObjectType that this Processor is for.
IResourceExtensionProcessorSource	getSource() return an appropriate instance of IResourceExtensionProcessorSource.
Resource	makeMyResource() generate an empty instance of the appropriate Resource class that this plugin expects to use for its Resources.
void	processArchiveEntries(IGetsArchiveEntries archive, Resource r) provides a way for the Pliny archive importer to give your access to data from its archive that you will want to store in a local cache.
boolean	processDrop(org.eclipse.swt.dnd.DropTargetEvent event) processes an object that has been dropped onto an ObjectType folder within the Resource Explorer.
void	setViewPart(org.eclipse.ui.part.ViewPart myViewPart) Pliny's Resource Explorer will make its ViewPart available to the implementor of this interface by calling this method at the time that this processor is setup by the Explorer.

Method Detail

setViewPart

public void setViewPart(org.eclipse.ui.part.ViewPart myViewPart)

Pliny's Resource Explorer will make its ViewPart available to the implementor of this interface by calling this method at the time that this processor is setup by the Explorer. Store it in your implementation if you need it for future use.

Parameters:

myViewPart -

getMyObjectType

public ObjectType getMyObjectType()

provides the ObjectType that this Processor is for. Pliny will look at the ObjectType associated with the Resource it is working with to decide which IResourceExtensionProcessor to invoke.

Returns:

ObjectType this processor will support

processDrop

public boolean processDrop(org.eclipse.swt.dnd.DropTargetEvent event)

processes an object that has been dropped onto an ObjectType folder within the Resource Explorer. Details about the dropped object are provided by the DropTargetEvent.

Parameters:

event -

canHandleObject

public boolean canHandleObject(Object data)

tests an object that has been dropped onto an ObjectType folder within the Resource Explorer to see if this object can process it. The object passed as a parameter is the data field in the DropTargetEvent.

Parameters:

data -

makeMyResource

public Resource makeMyResource()

generate an empty instance of the appropriate Resource class that this plugin expects to use for its Resources. The constructor should create an instance, but not write it to the DB. (Often this is the rdb2java object constructor with the parameter boolean realEmpty set to true, e.g. new Resource(true)). This is because this method is invoked on pre-existing DB resource data, and the caller within Pliny will fill data that has already been read from the DB into this created instance.

See Also:

PlinyXMLImporter

getSource

public IResourceExtensionProcessorSource getSource()

return an appropriate instance of IResourceExtensionProcessorSource.

Returns:

the appropriate IResourceExtensionProcessorSource

getContentFigure

public org.eclipse.draw2d.IFigure getContentFigure(Resource resource)

return an IFigure object that can be used to provide a 'content' display by Pliny. For resources that represent an image, this is likely to be an IFigure containing a thumbnail represention of that image.

Parameters:

resource - the Resource the IFigure should be about.

getCacheElements

public IResourceExtensionProcessor.CacheElement[] getCacheElements(Resource r)

provides access to cache data you want stored in the pliny archive file.

Returns:

an array of CacheElements that the the archiver what data is to be put in the archive file, and give a handle to a Stream that can provide it.

processArchiveEntries

public void processArchiveEntries(IGetsArchiveEntries archive,
                                  Resource r)
                           throws PlinyImportException

provides a way for the Pliny archive importer to give your access to data from its archive that you will want to store in a local cache.

Once the archive reader has invoked your caching code through this method, your code can request data for caching by calling IGetsArchiveEntries.getArchiveEntry(java.lang.String)

Parameters:

archive - IGetsArchiveEntries archive process that can provide you with access to input streams from the archive containing the data you want to put in the cache.

r - Resource the cache data should belong to.

Throws:

PlinyImportException