/**
* Vocabulary
* Copyright 2011 by Michael Peter Christen, mc@yacy.net, Frankfurt am Main, Germany
* First released 16.12.2011 at http://yacy.net
*
* $LastChangedDate: 2011-04-14 00:04:23 +0200 (Do, 14 Apr 2011) $
* $LastChangedRevision: 7653 $
* $LastChangedBy: orbiter $
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program in the file lgpl21.txt
* If not, see <http://www.gnu.org/licenses/>.
*/
package net.yacy.cora.lod;
import java.util.Set;
/*
* A Vocabulary is an interface to an 'extensible enum pattern'.
* We want to have an kind of extensible enum for vocabularies.
* Since enum classes cannot be extended we use a hack as explained in
* http://blogs.oracle.com/darcy/entry/enums_and_mixins .
* For an example for 'extensible enum pattern' see
* http://stackoverflow.com/questions/1414755/java-extend-enum
*/
public interface Vocabulary {
/**
* get the RDF identifier as an URL stub
* @return
*/
public String getNamespace();
/**
* get the prefix for the predicates of this vocabulary
* @return
*/
public String getNamespacePrefix();
/**
* get the predicate name which already contains the prefix url stub
* @return
*/
public String getPredicate();
/**
* The URI Reference as defined in http://www.w3.org/TR/rdf-concepts/ 2.2.3
* This is a combination of the namespace prefic and the constant name,
* concatenated with ':'.
* @return
*/
public String getURIref();
/**
* get a set of literals that are allowed for the predicate as values
* @return
*/
public Set<Literal> getLiterals();
/**
* the name method is identical to the java.lang.Enum method.
* If an Enum class for vocabularies
* implements this interface, the name() method is automatically implemented
*
* @return Returns the name of the enum constant as declared in the enum declaration.
*/
public String name();
}