/** Find the set of resources referenced by the path */
public static Set<RDFNode> getNodes(Model model, RDFNode first, Path path) {
List<Step> steps = path.getSteps();
Set<RDFNode> starts = Collections.singleton(first);
for (Step step : steps) {
String propertyName = step.getPropertyName();
boolean isInverse = step.isInverse();
Property property = model.createProperty(propertyName);
Set<RDFNode> nodes = new HashSet<RDFNode>();
for (RDFNode start : starts) {
Set<RDFNode> tmp;
if (!isInverse) {
tmp = model.listObjectsOfProperty(start.asResource(), property).toSet();
} else if (start.isResource()) {
tmp = new HashSet<RDFNode>(model.listSubjectsWithProperty(property, start).toSet());
} else {
tmp = Collections.<RDFNode>emptySet();
}
nodes.addAll(tmp);
}
starts = nodes;
}
return starts;
}
public static ArrayList<RdfModel> processRDF(InputStream in) {
Model model = ModelFactory.createDefaultModel();
ArrayList<RdfModel> result = new ArrayList<RdfModel>();
if (in != null) {
model.read(in, "RDF/XML");
// Now, I only care these propties: has-title, year-of, full-name. All three of them must
// exist'
for (final ResIterator it = model.listSubjectsWithProperty(RdfPropertyList.p_hasTitle);
it.hasNext(); ) {
RdfModel rm = new RdfModel();
try {
final Resource node =
it.next().asResource(); // node is a resource which has title property
rm.setHasTitle(node.getProperty(RdfPropertyList.p_hasTitle).getString());
StringBuilder authors = new StringBuilder();
StringBuilder dates = new StringBuilder();
for (final StmtIterator all_props = node.listProperties(); all_props.hasNext(); ) {
try {
Resource all_res = all_props.next().getObject().asResource();
StmtIterator fullnames = all_res.listProperties(RdfPropertyList.p_fullName);
StmtIterator years = all_res.listProperties(RdfPropertyList.p_year);
// Just for now I may have mutiple author or dates in a String, seperated by comma
RdfProcess newprocess = new RdfProcess();
while (fullnames.hasNext()) {
String fullname = newprocess.getValue(fullnames.next().getObject());
if (!fullname.equals("Invalid/Lack of Information")) {
authors.append(fullname + " , ");
}
}
while (years.hasNext()) {
String year = newprocess.getValue(years.next().getObject());
if (!year.equals("Invalid/Lack of Information")) {
dates.append(year + " , ");
}
}
} catch (Exception e) {
}
}
rm.setHasDate(dates.toString());
rm.setHasAuthor(authors.toString());
} catch (Exception e) {
}
result.add(rm);
}
}
return result;
}