图谱实践笔记4 - Jena实训

Model model = ModelFactory.createDefaultModel() ;
model.read("data.ttl") ;
// If the syntax is not as the file extension, a language can be declared
model.read("data.foo", "TURTLE") ;

// Create a model and read into it from file
// "data.ttl" assumed to be Turtle.
Model model = RDFDataMgr.loadModel("data.ttl") ;

// Create a dataset and read into it from file
// "data.trig" assumed to be TriG.
Dataset dataset = RDFDataMgr.loadDataset("data.trig") ;

// Read into an existing Model
RDFDataMgr.read(model, "data2.ttl") ;

 // The parsers will do the necessary character set conversion.  
try (InputStream in = new FileInputStream("data.some.unusual.extension")) {
     RDFParser.create()
    .source(in)
    .lang(RDFLanguages.TRIG)
    .errorHandler(ErrorHandlerFactory.errorHandlerStrict)
    .base("http://example/base")
    .parse(noWhere);
}

Query query = QueryFactory.create(queryString);
QueryExecution qExec = QueryExecutionFactory.create(query, model);
//QueryExecution qExec = QueryExecutionFactory.create(queryString, model);
System.out.println("Start execute query");
//Iterator<Triple> rs = qExec.execConstructTriples();
ResultSet results = qExec.execSelect();
List<QuerySolution> solutions = ResultSetFormatter.toList(results);
for(int i = 0; i < solutions.size(); i++){
    RDFNode objectNode= solutions.get(i).get("?object");
    String uri = objectNode.asResource().getURI();
    String localName = uri.substring(35).replace("/", "u0001");
    if("".equals(localName) || localName == null){
      count++;
      localName = "BlankNode_" + count;
}

File newFile = new File(output + localName + ".ttl");
FileWriter fw = new FileWriter(newFile);
BufferedWriter bw = new BufferedWriter(fw);
// the first query, find all statements starting with objectNode
Model model1 = model.listStatements(objectNode.asResource(), null, (RDFNode) null).toModel();
// the second query, find all statements ending with objectNode, an add operation is used for the two models
Model model2 = model1.add(model.listStatements(null, null, objectNode).toModel());
// write to files
model2.write(bw, "TURTLE");
bw.close();
fw.close();
}
System.out.println("Finish writing to file");
System.out.println("Final count:" + solutions.size());
dataset.close();

        File file = new File(inputDictionary);
        File[] fs = file.listFiles();
        model = ModelFactory.createDefaultModel(); // creates an in-memory Jena Model
        for(File f: fs){
            if(!f.isDirectory()){
//                System.out.println(f);
                try {
                    InputStream in = new FileInputStream(f.getAbsolutePath());
                    RIOT.init();
                    System.out.println(f.getAbsolutePath());
                    model.read(in, null, "TURTLE");
                    System.out.println(model.listStatements().toList().size());
//                    System.out.println("\n---- Turtle ----");
//                    model.write(System.out, "TURTLE");
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                }
            }
        }