CancelState Tracks the cancelation state of a cancelable operation. 
DateFormatter Allows the formatting of a date according to predefined formats. 
NamedLink An optionally-named link relating to an entity. 
Operation<T, E extends Throwable> Interface for operations carried out by services on behalf of plugins 
Page<T> Provides support for pagination. 
PagedCallback Marker interface augmenting a callback which produces a Page of results during its processing. 
PageRequest Pagination for a request. 
Progress A representation of the current progress of a task  
ProgressReporter A reporter for the current status of a task. 
UncheckedOperation<T> Convenience version of Operation that does not define a checked exception on its interface. 


AbstractPagedSummary Extends AbstractSummary and adds additional properties for summarizing a page of output. 
AbstractPagedSummary.AbstractPagedBuilder<B extends AbstractPagedBuilder<B, S extends AbstractPagedSummary>, S>  
AbstractSummary A base class for building summary objects that can be provided to callbacks when operations complete. 
AbstractSummary.AbstractBuilder<B extends AbstractBuilder<B, S extends AbstractSummary>, S>  
CustomPreconditions More precondition checks following the same pattern as Guava's Preconditions
FilteredPageImpl<T> An instance of Page that supports pagination across an underlying paged collection. 
PageRequestImpl Default implementation of PageRequest
ProgressImpl A default immutable implementation of the Progress interface. 
SimpleNamedLink A simple implementation of the NamedLink interface. 


DateFormatter.FormatType A predefined date format. 
Order Specifies the direction a list of results should be ordered - ascending or descending order.