org.apache.stanbol.entityhub.servicesapi.site
Interface EntityDereferencer

public interface EntityDereferencer

Service used by Site to dereference Representation for entity ids. Implementations of this interface are dependent on the service provided by the referenced site.

Author:

Rupert Westenthaler

Field Summary

static String

ACCESS_URI The key used to define the baseUri of the service used for the implementation of this interface. This constants actually uses the value of SiteConfiguration#ACCESS_URI

Method Summary

boolean	canDereference(String uri) Whether the parsed entity ID can be dereferenced by this Dereferencer or not. The implementation may not directly check if the parsed URI is present by a query to the site, but only check some patterns of the parsed URI.
Representation	dereference(String uri) Dereferences the Representation of the referred Entity
InputStream	dereference(String uri, String contentType) Generic getter for the data of the parsed entity id
String	getAccessUri() The base uri used to access this site

Field Detail

ACCESS_URI

static final String ACCESS_URI

The key used to define the baseUri of the service used for the implementation of this interface.
This constants actually uses the value of SiteConfiguration#ACCESS_URI

See Also:

Constant Field Values

Method Detail

getAccessUri

String getAccessUri()

The base uri used to access this site

Returns:

canDereference

boolean canDereference(String uri)

Whether the parsed entity ID can be dereferenced by this Dereferencer or not.
The implementation may not directly check if the parsed URI is present by a query to the site, but only check some patterns of the parsed URI.

Parameters:

uri - the URI to be checked

Returns:

true of URIs of that kind can be typically dereferenced by this service instance.

dereference

InputStream dereference(String uri,
                        String contentType)
                        throws IOException

Generic getter for the data of the parsed entity id

Parameters:

uri - the entity to dereference

contentType - the content type of the data

Returns:

the data or null if not present or wrong data type TODO: we should use exceptions instead of returning null!

Throws:

IOException

dereference

Representation dereference(String uri)
                           throws IOException

Dereferences the Representation of the referred Entity

Parameters:

uri - the uri of the referred entity

Returns:

the representation of null if no Entity was found for the parsed entity reference.

Throws:

IOException