This is a Java library for nanopublications (see http://nanopub.net) based on RDF4J.

It implements the formal structure defined in the official nanopublication guidelines.

The easiest way to use this library in your project is to let Maven download it from The Central Repository, with an entry in your pom.xml file as shown here.

Alternatively, you might want to use one of the pre-built jar files.

In a nutshell, to create and publish nanopublications, you need to first make sure you have a local keypair. To create such a keypair, run just once:

    MakeKeys.make("~/.nanopub/id", SignatureAlgorithm.RSA);

And then nanopublications can be created and published programmatically like this:

    System.err.println("# Creating nanopub...");
    NanopubCreator npCreator = new NanopubCreator(true);
    final ValueFactory vf = SimpleValueFactory.getInstance();
    final IRI anne = vf.createIRI("https://example.com/anne");
    npCreator.addAssertionStatement(anne, RDF.TYPE, vf.createIRI("https://schema.org/Person"));
    npCreator.addProvenanceStatement(PROV.WAS_ATTRIBUTED_TO, anne);
    npCreator.addPubinfoStatement(RDF.TYPE, vf.createIRI("http://purl.org/nanopub/x/ExampleNanopub"));
    Nanopub np = npCreator.finalizeNanopub(true);
    System.err.println("# Nanopub before signing:");
    NanopubUtils.writeToStream(np, System.err, RDFFormat.TRIG);

    System.err.println("# Signing nanopub...");
    Nanopub signedNp = SignNanopub.signAndTransform(np, TransformContext.makeDefault());
    System.err.println("# Final nanopub after signing:");
    NanopubUtils.writeToStream(signedNp, System.err, RDFFormat.TRIG);

    System.err.println("# Publishing to test server...");
    PublishNanopub.publishToTestServer(signedNp);
    //System.err.println("# Publishing to real server...");
    //PublishNanopub.publish(signedNp);
    System.err.println("# Published");

For the complete code checkout UsageExamples.java.

To use this library on the command line, just download the np script. Make sure it is executable and then you can invoke it with ./np ... (or simply np ... if you make sure it's included in the PATH variable), for example:

./np check nanopubfile.trig

This automatically downloads the latest release as a jar file on the first run. You can also directly use the prebuilt jar files:

java -jar nanopub-1.67-jar-with-dependencies.jar check nanopubfile.trig

Note: For Mac users, before running np ensure that the GNU version of curl is installed (not the default BSD versions), and are the ones being used when the curl command is invoked.

You can use this image from DockerHub.

Sign a nanopublication (nanopub.trig file in current dir here):

docker run -it --rm -v ~/.nanopub:/root/.nanopub -v $(pwd):/data nanopub/nanopub-java sign /data/nanopub.trig

Publish a signed nanopublication:

docker run -it --rm -v ~/.nanopub:/root/.nanopub -v $(pwd):/data nanopub/nanopub-java publish /data/signed.nanopub.trig

Build the Docker image:

docker build -t nanopub/nanopub-java .

Maven has to be installed to compile the library:

mvn clean package

The library features can then be accessed by calling scripts/run.sh (with the same commands as for the np script above, but using the locally compiled code and not the jar file).

Create the file target/jacoco.exec which includes the test coverage information in a binary format.

mvn clean verify

To create a html report out of jacoco.exec (target/site/jacoco/index.html) use:

mvn jacoco:report

• Tobias Kuhn. nanopub-java: A Java Library for Nanopublications. In Proceedings of the 5th Workshop on Linked Science (LISC 2015). 2015.

nanopub-java is free software under the MIT License. See LICENSE.txt.