如何从dbpedia链接或URL检索XML / RDF数据？

Question

Recently I have been trying to learn Semantic Web. For a project I need to retrieve data from a given dbPedia link. eg http://dbpedia.org/page/Berlin . But when retrieve data using java.net.URLConnection I get the html data. How can I get the xml from the same link ? I know that there is link in every dbpedia page to download the XML but that is not what I want to do. Thanks in advance.

Answer 1

Note that the URI of the resource is actually http://dbpedia.org/resource/Berlin (with resource , not page ). Ideally, you could request that URI with an Accept header of application/rdf+xml and get the RDF/XML representation of the resource. That's how the BBC publishes their data (eg, see this answer ), but DBpedia doesn't do that. Even if you request application/rdf+xml, you end up getting a redirect. You can see if you try with an HTTP client. Eg, using Advanced Rest Client in Chrome, we get this 303 redirect:

In a web browser, you get redirected to the page version by a 303 See Other response code. Ideally, you could request the resource URI with the accept header set to application/rdf+xml and get the data, but DBpedia doesn't place quite so nicely.

So, that means that the easiest way is to note that at the bottom of http://dbpedia.org/page/Berlin , there's the text with some download links:

RDF ( N-Triples N3/Turtle JSON XML )

The URL of the last link is http://dbpedia.org/data/Berlin.rdf . Thus, you can get the RDF/XML by changing page or resource to data , and appending .rdf to the end of the URL. It's not the most ReSTful solution, but it seems to be what's available.

Answer 2

The good to access data from dbpedia is through Sparql . You can use Apache Jena to run sparql queries against http://dbpedia.org/sparql