Java - Jena API - Getting more than one datatypeproperty

Question

I'm using Java and Jena API. I have a class Marriage which have 3 Object Properties called "hasHusband", "Haswife" and "dateOfMarriage". The first two are associated with a class Person which has the datatypeproperties hasFirstName, hasLastName, dateOfBirth....

Through the code below I can access the hasFirstName property of the husband.

StmtIterator iter = onto.model.listStatements(null,onto.hasHusband,(RDFNode)null);  
while (iter.hasNext()) {
    Statement stmt = iter.nextStatement();  
    Resource P = ((Resource) stmt.getObject());

    StmtIterator iter2 = onto.model.listStatements(((Resource) P),onto.hasFirstName,(RDFNode)null);  
    while (iter2.hasNext()) {
         Statement stmt2 = iter2.nextStatement();  
         firstnameHusband = stmt2.getObject().toString();
    }}

I would like to modify this line

 StmtIterator iter2 = onto.model.listStatements(((Resource) P),onto.hasFirstName,(RDFNode)null);  

in order to access also the hasLastName and hasDateofBirth...

Can you explain me how can I do this?

Thanks

EDITED: @Pierre Now it concerns only the class Person. In case of womans I want to output in a new file (text file) this line below for each woman:

[label= \"" +firstName+ " \"\n\n\"D.Naiss:"+dnai1+"\", "+shape2+"]

And for each man this:

[label= \"" +firstName+ " \"\n\n\"D.Naiss:"+dnai1+"\", "+shape+"]

The diference is in the value of shape. The problem I have is that he only outputs one woman and one man.

A person is represented like this in my rdf file:

  <rdf:Description rdf:about="http://www.fam.com/FAM#Bruno04/02/1980 ">
    <j.0:FAMhasGender>H</j.0:FAMhasGender>
    <j.0:FAMhasDateOfBirth>04/02/1980</j.0:FAMhasDateOfBirth>
    <j.0:FAMhasLastName>DS </j.0:FAMhasLastName>
    <j.0:FAMhasFirstName> Bruno</j.0:FAMhasFirstName>
  </rdf:Description>

Here is the relevant code:

public void accessProp() {

    readFile(inputFile); // rdf
    String fname;
    String dd;
    String gen;

    ExtendedIterator instances = onto.person.listInstances();
    Individual instance = null;
    Individual firstInstance = null;
    while (instances.hasNext()) {
        instance = (Individual) instances.next();

        gen = instance.getPropertyValue(onto.hasGender).toString();
        fname = instance.getPropertyValue(onto.hasFirstName).toString();
        dd = instance.getPropertyValue(onto.hasDateOfBirth).toString();

        writeFile(fname, dd, genr);
    }
}

// Write text file
public void writeFile(String fn, String dbir, String gn) {
    String fileout = "D:/file1.txt";
    String firstName = fn;
    String dateB = dbir;
    String gender = gn;

    BufferedWriter out;
    try {
        out = new BufferedWriter(new FileWriter(fileout, true));

        if (gender.equals("F")) {
            out.write("[label= \"" + firstName + " \"\n\n\"D.Naiss:" + dnai1 + "\", " + shape + "]");
        }

        else if (gender.equals("M")) {
            out.write("[label= \"" + firstName + " \"\n\n\"D.Naiss:" + dnai1 + "\", " + shape2 + "]");
        }

        out.newLine();

        // flushes and closes the stream
        out.close();
    } catch (IOException e) {
        System.out.println("There was a problem:" + e);
    }
}

Can you tell me what should I do to solve my problem?

Thanks

Answer 1

create a helper function to get a specific property:

public RDFNode getProperty(Resource subject,Property prop)
   {
   RDFNode object=null;
   StmtIterator iter2 = this.onto.model.listStatements(subject,prop,(RDFNode)null);  
    while (iter2.hasNext()) {
         object = iter2.nextStatement().getObject();
         break;
    }}
   iter2.close();
   return object;
   }

public String getPropertyAsString(Resource subject,Property prop)
   {
   RDFNode object=getProperty(subject,prop);
   return object==null?null:object.toString();
   }

(...)
String s1=getPropertyAsString(P,onto.hasFirstName);
String s2=getPropertyAsString(P,onto.hasLastName);
(...)