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h1. Access Methods

OWLIM is packaged as a Storage and Inference Layer (SAIL) for [Sesame version 2.x|] and makes extensive use of the features and infrastructure of Sesame, especially the RDF model, RDF parsers and query engines. Explicit and inferred statements are stored in highly-optimized data structures. The inferred closure is updated through inference at the end of each transaction that modifies the repository.
OWLIM implements the Sesame SAIL interface so that it can be integrated with the rest of the Sesame framework, e.g. the query engines and the web user interface tools. A typical user application uses OWLIM directly through the Sesame SAIL API. When an OWLIM repository is exposed using the Sesame HTTP Server, users can manage the repository through the Sesame Workbench Web application, or with other tools that can integrate with Sesame, e.g. ontology editors like TopBraid Composer.
Sesame comprises a large collection of libraries, utilities and APIs, but the important components for this section are:
* the Sesame classes and interfaces (API) that provide uniform access to SAIL components from multiple vendors/publishers;
* the Sesame server and workbench Web applications (Java Enterprise Edition servlet components, referred to on the diagram above as "Sesame Web UI").

This section will describe using the Sesame API to create and access OWLIM-Lite repositories, both on the local file-system and remotely via the Sesame HTTP server. Furthermore, a brief introduction will be given to the Sesame workbench Web application that provides many repository management functions through a convenient user interface.

h1. Sesame Application Programming Interface (API)

Programmatically, OWLIM is used via the Sesame Java framework of classes and interfaces. Documentation for these interfaces (including Javadoc) can be found at [|]. Code snippets in the following sections are taken from (or are variations of) the GettingStarted example program that comes with the OWLIM-Lite distribution.

h2. Using the Sesame API to access a local OWLIM repository

With Sesame 2, repository configurations are represented as RDF graphs. A particular repository configuration is described as a resource, possibly a blank node, of type:
This resource has an 'id', a label and an implementation, which in turn has a type, SAIL type, etc. The example repository configuration from the getting-started example program looks like this:
@prefix rdfs: <>.
@prefix rep: <>.
@prefix sr: <>.
@prefix sail: <>.
@prefix owlim: <>.

[] a rep:Repository ;
rep:repositoryID "owlim" ;
rdfs:label "OWLIM Getting Started" ;
rep:repositoryImpl [
rep:repositoryType "openrdf:SailRepository" ;
sr:sailImpl [
sail:sailType "swiftowlim:Sail" ;
owlim:ruleset "owl-horst-optimized" ;
owlim:noPersist "true" ;
owlim:storage-folder "storage" ;
owlim:base-URL "" ;
owlim:new-triples-file "new-triples-file.nt" ;
owlim:entity-index-size "200000" ;
owlim:jobsize "200" ;
owlim:repository-type "in-memory-repository" ;
owlim:imports "./ontology/owl.rdfs " ;
owlim:defaultNS "" .
The Java code to use the configuration to instantiate a repository and get a connection to it is as follows:
Graph graph = ...;
Resource repositoryNode = ...;

// Create a manager for local repositories
RepositoryManager repositoryManager =
new LocalRepositoryManager(new File("."));

// Create a configuration object from the configuration graph
// and add it to the repositoryManager
RepositoryConfig repositoryConfig =
RepositoryConfig.create(graph, repositoryNode);

// Get the repository to use
Repository repository = repositoryManager.getRepository("owlim");

// Open a connection to this repository
RepositoryConnection repositoryConnection =

// ... use the repository

// Shutdown connection, repository and manager
Note that the code to parse this file and find the 'root' node for the configuration can be found in the getting-started program.
The procedure is as follows: instantiate a local repository manager with the data directory to use for the repository storage files (repositories will store their data in their own sub-directory from here), add a repository configuration for the desired repository type to the manager, 'get' the repository and open a connection to it. From then on, most activities will use the connection object to interact with the repository, e.g. executing queries, adding statements, committing transactions, counting statements, etc. See the getting-started application for examples.

h2. Using the Sesame API to access a remote OWLIM repository

The Sesame Server is a Web application that allows interaction with repositories using the HTTP protocol. It runs in a JEE compliant servlet container, e.g. Tomcat, and allows client applications to interact with repositories located on remote machines. All that is required to connect to and use a remote repository instead of a local one is to replace the local repository manager for a remote one. The URL of the Sesame Server must be provided, but no repository configuration is needed if the repository already exists on the server. The following lines can be added to the getting-started example program, although a correct URL must be specified:
{code:title=Example to create a connection to a remote repository|borderStyle=solid}RepositoryManager repositoryManager =
new RemoteRepositoryManager( "" );
{code}The rest of the example program should work as expected, although the following library files must be added to the class-path:
* {{commons-httpclient-3.1.jar}}
* {{commons-logging-1.1.1.jar}}
* {{commons-codec-1.3.jar}}

h1. Managing repositories with the Sesame Workbench

The [installation section|OWLIMv40:OWLIM-Lite Installation] explains how to set up a OWLIM-Lite repository that is exposed via the Sesame HTTP Server. In summary, the Sesame Server and Workbench applications are deployed to a Tomcat instance and the necessary library files are copied to the correct locations. After this, the Sesame console application is used with the {{owlim-lite.ttl}} repository template file to connect to the Sesame server and create a repository instance.
When the Sesame server is running, it will show a welcome message at the following URL:
The server has a simple user interface that shows status, logging and configuration information.
The workbench application, however, provides most repository management functions and is available from the following URL:
noformat}http:// <hostname|ip_address>:8080/openrdf-workbench{noformat}
The workbench lists repositories and their namespaces, allows for the addition and deletion of statements, and provides a query interface for SPARQL and SeRQL query languages. However, the list of repository types is currently hard-coded in the workbench, so an OWLIM repository must still be created using the Sesame console application, as described in the [installation section|OWLIM-Lite Installation].