= Presentation Layer API

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Domain service APIs for the presentation layer allow the domain objects to control aspects of the user interface.


.Presentation Layer API
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|===

|API
|Description


|xref:refguide:applib:index/services/acceptheader/AcceptHeaderService.adoc[AcceptHeaderService]
|Request-scoped access to HTTP Accept headers.

|xref:refguide:applib:index/services/bookmarkui/BookmarkUiService.adoc[BookmarkUiService]
|Manage bookmarks and breadcrumbs.

|xref:refguide:applib:index/services/linking/DeepLinkService.adoc[DeepLinkService]
|Obtain a URL to a domain object (eg for use within an email or report)



|===


CAUTION: The implementations are specific to the particular viewer (xref:vw:ROOT:about.adoc[Web UI (Wicket viewer)] or xref:vro:ROOT:about.adoc[REST API (Restful Objects viewer)]) so domain code must guard against them being unavailable in some cases.


