From NSDLWiki

NDR Access and Filtering

Default class implementing NDRAccess: BasicFedoraNDRAccess OR is it FilteredNDRAccess

Commonly used methods:

• getObject(NDRObjectInfo)
• getObject(NDRObjectInfo,Type)
• getObject(String,Type)
• getObject(PID)
• getObject(String)

• newObject(Type)

• openObject(NDRObjectInfo)

All return either...

• repository.model.types.TypeFactory factory.instantiate(getObject(NDRObjectInfo),Type<T>) which returns an object that extends repository.model.NDRObject interface
  • repository.impl.
• OR repository.impl.fedora.MutableAPIFedoraObject

• deleteObject(NDRObjectInfo)
• purgeObject(NDRObjectInfo)

when you use NDRAccess object, the filters get called when you do certain things

• • calls NDR access filters that check content model, assign handles, data processing and cleaning, etc. (in org.nsdl.repository.api.request.filters)

NDRAccess:

• interface
• requires methods for...
  • getObject
  • newObject
  • deleteObject
  • purgeObject
  • getObjectFinder
  • isReadOnly

FilteredNDRAccess

• use of this class is configured
• implements NDRAccess
• runFilters(FilterState state)
  • which calls FilteredNDRAccess.FilterManager.invoke(NDRObject,FilterContext)
  • which calls <NDRAccessFilter>filter.doFilter(NDRObject,FilterContext)
• initializeFilters(Configuration)
  • Configuration file lists the filters to be added
  • calls FilteredNDRAccess.FilterManager.addFilter(NDRAccessFilter) for each filter listed in the config file
• updateConfig(Configuration)
  • calls initializeFilters(Configuration)

NOTE: Java Toolkit is configured to use InterpretedNDRAccess instead of FedoraNDRAccess.

NDRAccessFilter

• interface
• extends nothing and implements nothing
• used by FilteredNDRAccess for adding and running filters

getObject() StaticObjectInfo(handle) NDRObjectTemplate(Type) , where Type = Agent | Aggregator | Metadata, etc.