jobc-driver

Jobc (java ontology base connection)

LOD, Apache Jena Fuseki, Virtuoso can be used in Java just like JDBC.

Features

• Execute Sparql on ontology repositories by coding like a general Database Connection.
• PoolManager is available. (LOD and Fuseki do not manage the actual pool).
• Can be used like Mybatis.
• The same Sparql can be used in LOD, Jena fuseki, and Virtuoso. When using Preparedstatement, '? ' is used as a variable in Sparql just like in Sql.
• When using preparedstatement in Virtuoso, Sparql uses a different method.
  • e.g.) Use parameters as '??' or use 'INSERT INTO GRAPH' for 'INSERT Data'.
• Generally, LOD does not support updates.

JobcDriver Attrebute Value

Divier Name : com.frotoma.jobc.JobcDriver URL : Ontology Storage Address user : User ID password : User password

URL Attrebute Value

jobc:[Ontology Storage Type]:[Ontology Storage Address]&method=[HTTP Verbs]

• Ontology Storage Type
  • LOD : web
  • Fuseki : fuseki
  • Virtuoso : virtuoso
• Ontology Storage Address
  • LOD : web address
    • ex)

    http://localhost:8080/sparql
    

  • Fuseki : Web address
    • ex)

    http://localhost:3030/jobc/sparql
    

  • Virutoso : address
    • ex)

    localhost:1111/CHARSET=UTF-8
    

• HTTP Verbs : API HTTP Method
  • ex) get, post etc...
• Full Example
  • LOD : jobc:web:http://localhost:3030/jobc/sparql&method=post
  • Fuseki : jobc:fuseki:http://localhost:3030/jobc/sparql&method=post
  • Virtuoso : jobc:virtuoso://localhost:1111/CHARSET=UTF-8

Preparedstatement

• The code is identical to using JDBC.
• '?' is used as a variable in Sparql.

Preparedstatement Example

        String preparedSql = 
            "SELECT *  WHERE {  " +
            "  Filter( ?person = ? ) . " +
            "  ?person ? ?member . " +
            "  ?member <http://dbpedia.org/property/name> ?membername ." +
            "}  ";

        String DRIVER = "com.frotoma.jobc.JobcDriver";
        String URL = "jobc:web:http://dbpedia.org/sparql/";
        String user = null;
        String password = null;

        Connection connection = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        try {
            DataSource dataSource = crateDataSource();
            connection = dataSource.getConnection();            
            stmt = connection.prepareStatement(preparedSql);

            stmt.setObject(1, ParamBuilder.createIRI("http://dbpedia.org/resource/BTS"));
            stmt.setObject(2, ParamBuilder.createIRI("http://dbpedia.org/ontology/bandMember") );
            //stmt.setString(2, "South Korea");
            
            rs = stmt.executeQuery();            
            
            ResultSetMetaData rsm = stmt.getMetaData();
            int columnCount = rsm.getColumnCount();
            
            
            System.out.println("============================================== ");
            
            System.out.print("NUM");
            for( int i = 0; i< columnCount; i++ ){
                System.out.print( "\t" );
                System.out.print( rsm.getColumnLabel(i+1) );                    
            }
            System.out.println("");            
            System.out.println("---------------------------------------------- ");

            int num = 0;
            while (rs.next()) {
                System.out.print( num );
                for( int i = 0; i< columnCount; i++ ){
                    System.out.print( "\t" );
                    System.out.print( rs.getString(i+1) );
                }
                System.out.println("");
                num++;
            }

        } catch (Exception e) {
            try {
                connection.rollback();
            } catch (SQLException e1) {
                e1.printStackTrace();
            }
            e.printStackTrace();
        }

Contact

• Email : jongearl@frotoma.com
• Company : 프로토마