Linked data from your pocket: The Android RDFContentProvider
Jérôme David, Jérôme Euzenat · 2010
Smartphones are becoming main personal information repositories. Unfortunately this information is stored in independent silos managed by applications. We have seen that already: in the Palm operating system, application “databases ” were only accessible when the application schemas were known and worked by opening other application databases. Our goal is to provide support for applications to deliver their data in RDF. This would allow applications to exploit this information in a uniform way without knowing beforehand application schemas. This would also connect this information to the semantic web and the web of data through reference from and to device information. We present a way to do this in a uniform manner within the Android platform. Moreover, we propose to do it along the linked data principles (provide RDF, describe in ontologies, use URIs, link other sources). We first consider how the integration of RDF could be further pushed within the context of the Android platform. We demonstrate its feasibility through a linked data browser that allows for browsing the phone information. 1 Providing RDF support in Android Android is built around different kinds of services, one of which being ContentProvider which exposes some data of an application to other applications. ContentProviders manage data structures (usually relational tables) and are able to answer messages of type query, insert, delete and update. A query returns a cursor on a table of tuples. So they offer a typical database interface: Cursor query ( Uri id, String[] proj, String select, String[] selectArgs, String order) Uri insert ( Uri id, ContentValues colValueList) int update ( Uri id, ContentValues colValueList, String select, String[] selectArgs)