Announcing Spring Jena

On the heels of Groovy SPARQL, here is an initial code base for standard Java and Spring applications -- Spring Jena!

The Spring folks have been putting together an impressive portfolio of data oriented capabilities for NoSQL data stores.  To compliment the those capabilities, here is Spring Jena - a project I hope to propose back to the Spring community to provide direct Jena API support and direct SPARQL.

Much like Groovy SPARQL, this is a relatively simple code base that applies the template design pattern to Jena and ARQ to simplify every day needs for creating, modifying, and querying RDF data.  There is a lot more work to do here, most noteably the parameterized queries.

Get Spring Jena @ Github here.

The roadmap includes:

• Spring datastore/mapping support for object relational mapping, once those projects reach 1.0
• Spring Transaction support - wrap Jena native transactions or provide app-level transaction management via Spring
• Abstraction for triple stores - likely aligned against the Datastore interface in Spring Data
• QuerySolutionMap overloading to the methods in the SparqlTemplate
• Web / MVC capabilities, such as a taglib

Here is a GIST to get you going:

	package com.example;
	import org.springframework.data.rdf.sparql.*;
	import org.springframework.data.rdf.jena.*;
	import org.junit.Before;
	import org.junit.Test;
	public class TestSpringJena {
	private Model model;
	private JenaTemplate jena;
	private SparqlTemplate sparql;
	@Before
	public void init() {
	model = ModelFactory.createDefaultModel();
	jena = new JenaTemplate();
	sparql = new SparqlTemplate();
	jena.setModel(model);
	sparql.setModel(model);
	}
	@Test
	public void testModel() {
	jena.add("urn:test", "urn:someProperty", "hello world");
	// Select by list
	String query1 = "SELECT ?x ?y ?z WHERE { ?x ?y ?z }";
	List<String> list = sparql.execSelectList(query1, new SolutionMapper<String>() {
	public String mapSelect(ResultSet rs, int rowNum) {
	QuerySolution sln = rs.nextSolution();
	RDFNode x = sln.get("x");
	RDFNode y = sln.get("y");
	RDFNode z = sln.get("z");
	return x.toString() + "|" + y.toString() + "|" + z.toString();
	} });
	// result set as a map of strings
	Map<String, String> map = sparql.execSelectStringMap(query1);
	// Need one parameter? select a string
	String query2 = "SELECT ?z WHERE { <urn:test> ?y ?z }";
	String result = sparql.execSelectString(query2);
	}
	}

view raw TestSpringJena.java hosted with ❤ by GitHub

Enjoy!