I have opened my ontology so far and now I want to read all the objects and display their properties:
I have the next code:
// Opening the ontology.
OntModel model = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM);
model.read("file:C:/Users/Antonio/Desktop/myOntology.owl","OWL");
// Going through the ontology
for (Iterator<OntClass> i = model.listClasses();i.hasNext();){
OntClass cls = i.next();
System.out.print(cls.getLocalName()+": ");
// here I want to show the properties
}
which just shows the name of the classes, but not their properties.
I have been reading the documentation but I don't find anything useful.
Hopefully someone can help me.
Thanks in advance.
I'm not sure why you would want all the properties but you can do that easily. First of all make sure to import Jena's OntProperty import org.apache.jena.ontology.OntProperty;
Then you can simply inside your for loop : cls.listDeclaredProperties().toList()
If you want to access the content of a specific property though you could do it this way :
Check your .owl file for the URI which generally looks something like this "http://example.com/ontology#"
So your Java code is going to look like this : OntProperty nameOfProperty = model.getOntProperty("http://example.com/ontology#nameOfyourProperty");
Then inside your loop you could do for example something like this : cls.getProperty(nameOfProperty).getString()
And by the way before reading your file you might want to put it in a try catch statement. Hope that helped.
The code is printing classes because listClasses() returns classes of the ontology. For printing the object properties of the individuals, you can use OWL API
Related
EDIT: I changed my mind. I would find a way to generate the Java class and load the JSON as an object of that class.
I just discovered that exists a variant of JSON called JSON-LD.
It seems to me a more structured way of defining JSON, that reminds me XML with an associated schema, like XSD.
Can I create a Java class from JSON-LD, load it at runtime and use it to convert JSON-LD to an instantiation of that class?
I read the documentation of both the implementations but I found nothing about it. Maybe I read them bad?
Doing a Google search brought me to a library that will decode the JSON-LD into an "undefined" Object.
// Open a valid json(-ld) input file
InputStream inputStream = new FileInputStream("input.json");
// Read the file into an Object (The type of this object will be a List, Map, String, Boolean,
// Number or null depending on the root object in the file).
Object jsonObject = JsonUtils.fromInputStream(inputStream);
// Create a context JSON map containing prefixes and definitions
Map context = new HashMap();
// Customise context...
// Create an instance of JsonLdOptions with the standard JSON-LD options
JsonLdOptions options = new JsonLdOptions();
// Customise options...
// Call whichever JSONLD function you want! (e.g. compact)
Object compact = JsonLdProcessor.compact(jsonObject, context, options);
// Print out the result (or don't, it's your call!)
System.out.println(JsonUtils.toPrettyString(compact));
https://github.com/jsonld-java/jsonld-java
Apparently, it can take it from just a string as well, as if reading it from a file or some other source. How you access the contents of the object, I can't tell. The documentation seems to be moderately decent, though.
It seems to be an active project, as the last commit was only 4 days ago and has 30 contributors. The license is BSD 3-Clause, if that makes any difference to you.
I'm not in any way associate with this project. I'm not an author nor have I made any pull requests. It's just something I found.
Good luck and I hope this helped!
see this page: JSON-LD Module for Jackson
I want to be able to read ID3v2 tags from mp3 files. I have found multiple frameworks which allow me to get the basic tags. But I would like to be able those in this list. I don't care about backwards compatibility with IDv1.
I already had a look at Jaudiotagger and mp3agic. I didn't find out how to use them for custom tags. Is this possible?
You've to use the string identifier "TXXX", that's the main difference between "normal" and custom fields. I think the following code should be self-explanatory:
AudioFile audioFile = AudioFileIO.read(File songFile) // try and catch
MP3File mp3 = (MP3File) audioFile;
AbstractID3v2Tag v2Tag = mp3.getID3v2Tag();
// Since you've mentioned a list
List<TagField> tagList = v2Tag.getFields("TXXX")
That's one way to do it. The List has now all tags with the TXXX identifier. Now you can simply call toString() on every element in the list and you should get something along those lines:
Description="Play Count"; Text="1.000.000"
(After months of surfing the internet, talking to the school's computing department and try code out, I still don't get how to do it, but I do know more specific about what I trying to do)
Previously I said I want to "Add lines" to a existing JSON file.
What I want to do is simply add an element to an JSON object from a file, then save the file.
However I am still confused about how to do it.
The process I am guessing is to use ajax to load the content of the file (the JSON code in the file) into a variable then add the new element into the object then save the file.
I have seen a lot of code but are all just too confusing and looks like its for webpages. I am trying to edit a file on the computer as a program which I think webpage related code such as xmlhttp requests are irrelevant as the file is in a folder in appdata.
I have been confused and thought Java and Javascript were the same thing, I know now they're not.
What code or functions would I look for and how would it be used in the code?
(Please don't post pseudocode because I have no idea how to write the code for them since I have literally no idea how to code anything other than a html webpage and some php. Other coding language like Java, Javascript and Python I have little knowledge with but not enough to write a program alone.)
I think it would be best to use code that somebody else has already written to manipulate the JSON. There are plenty of libraries for that, and the best would be the officially specified one, JSON-P. What you would do is this:
Go to http://jsonp.java.net/ and download JSON-P. (You will have to examine the page carefully to find the link to "JSON Processing RI jar".) You will need to include this JAR in your class path while you write your program.
Add imports to your program for javax.json.*.
Write this code to do the job (you will have to catch JsonExceptions and IOExceptions):
JsonReader reader = Json.createReader(new FileReader("launcher_profiles.json"));
JsonObject file = reader.readObject();
reader.close();
JsonObject profiles = file.getJsonObject("profiles");
JsonObject newProfile = Json.createObjectBuilder()
.add("name", "New Lines")
.add("gameDir", "New Lines")
.add("lastVersionId", "New Lines")
.add("playerUUID", "")
.build();
JsonObjectBuilder objectBuilder = Json.createObjectBuilder()
.add("New Profile Name", newProfile);
for (java.util.Map.Entry<String, JsonValue> entry : profiles.entrySet())
objectBuilder.add(entry.getKey(), entry.getValue());
JsonObject newProfiles = objectBuilder.build();
// Now, figure out what I have done so far and write the rest of the code yourself! At the end, use this code to write out the new file:
JsonWriter writer = Json.createWriter(new FileWriter("launcher_profiles.json"));
writer.writeObject(newFile);
writer.close();
I am using the apache commons configuration library to read a configuration xml and it works nicely. However, I am not able to modify the value of the elements or add new ones.
To read the xml I use the following code:
XMLConfiguration config = new XMLConfiguration(dnsXmlPath);
boolean enabled = config.getBoolean("enabled", true));
int size = config.getInt("size");
To write I am trying to use:
config.setProperty("newProperty", "valueNewProperty");
config.save();
If I call config.getString("newProperty"), I obtain "valueNewProperty", but the xml has not been changed.
Obviously it is not the right way or I am missing something, because it does not work.
Could anybody tell me how to do this?
Thanks in advance.
You're modifying xml structure in memory
The parsed document will be stored keeping its structure. The class also tries to preserve as much information from the loaded XML document as possible, including comments and processing instructions. These will be contained in documents created by the save() methods, too.
Like other file based configuration classes this class maintains the name and path to the loaded configuration file. These properties can be altered using several setter methods, but they are not modified by save() and load() methods. If XML documents contain relative paths to other documents (e.g. to a DTD), these references are resolved based on the path set for this configuration.
You need to use XMLConfiguration.html#save(java.io.Writer) method
For example, after you've done all your modifications save it:
config.save(new PrintWriter(new File(dnsXmlPath)));
EDIT
As mentioned in comment, calling config.load() before calling setProperty() method fixes the issue.
I solved it with the following lines. I was missing the config.load().
XMLConfiguration config = new XMLConfiguration(dnsXmlPath);
config.load();
config.setProperty("newProperty", "valueNewProperty");
config.save();
It is true though that you can used the next line instead of config.save() and works the same.
config.save(new PrintWriter(new File(dnsXmlPath)));
I have about 3200 URLs to small XML files which have some data in the form of strings(obviously).The XML files are displayed(not downloaded) when I go to the URLs. So I need to extract some data from all those XMLs and save it in a single .txt file or XML file or whatever. How can I automate this process?
*Note: This is what the files look like. I need to copy the 'location' and 'title' from all of them and put them in one single file. Using what methodology can this be achieved?
<?xml version="1.0"?>
-<playlist xmlns="http://xspf.org/ns/0/" version="1">
-<tracklist>
<location>http://radiotool.com/fransn.mp3</location>
<title>France, Paris radio 104.5</title>
</tracklist>
</playlist>
*edit: Fixed XML.
It's easy enough with XQuery or XSLT, though the details will depend on how the URLs are held. If they're in a Java List, then (with Saxon at least) you can supply this list as a parameter to the following query:
declare variable urls as xs:string* external;
<data>{
for $u in $urls return doc($u)//*:tracklist
}</data>
The Java code would be something like:
Processor proc = new Processor();
XQueryCompiler c = proc.newXQueryCompiler();
XQueryEvaluator q = c.compile($query).load();
List<XdmItem> urls = new ArrayList();
for (url : inputUrls) {
urls.append(new XdmAtomicValue(url);
}
q.setExternalVariable(new QName("urls"), new XdmValue(urls));
q.setDestination(...)
run();
Have a look at the JSoup library here: http://jsoup.org/
It has facilities for pulling and fixing the contents of a URL, it is intended for HTML though, so I'm not sure it will be good for XML, but it is worth a look.