/SPARQL-parser

Primary LanguageJavaMIT LicenseMIT

SPARQL parser

The SPARQL parser is a library that helps to parse and investigate a SPARQL query and to build up and generate SPARQL queries.

Usage

To parse a query you can run:

SPARQLQuery parsedQuery = new SPARQLQuery("SELECT * FROM <http://graph1> WHERE { ?s ?p ?o . }");

The parsedQuery object will then contain a java object representation of that query. It will have a hashMap with prefix objects, a type , a list of IStatements, a set of unknowns, possibly a graph and the original query.

Prefix objects

Those are quiet simple, they map a name on a URL.

Type

The following types are supported

  • SPARQLQuery.Type.ASK
  • SPARQLQuery.Type.DESCRIBE
  • SPARQLQuery.Type.SELECT
  • SPARQLQuery.Type.CONSTRUCT
  • SPARQLQuery.Type.UPDATE

IStatement

The IStatement interface is an abstraction of SPARQL statements. It includes 'select blocks', 'where blocks', 'update blocks', 'parentheses blocks' and 'simple statements'. These blocks support methods to extract the unknowns, inner blocks (for instance a select block contains a parentheses block and that again contains multiple simple statements), the graph on which it operates as well as some functional methods (to change the graph for instance).

Unknown

This is just a java String that holds the name of the variable in the query without the '?' (ie. ?mu becomes "mu")

Graph

This is also just a java String.

Installation

Adding to the pom:

<dependency>
  <groupId>com.tenforce.semtech</groupId>
  <artifactId>SPARQL-parser</artifactId>
  <version>0.0.3</version>
</dependency>