import de.fuberlin.wiwiss.d2rq.ResourceDescriber; //导入依赖的package包/类
public void start() {
	startupError = true;
	if (config.isLocalMappingFile()) {
		this.dataset = new AutoReloadableDataset(loader,
				config.getLocalMappingFilename(),
				config.getAutoReloadMapping());
	} else {
		this.dataset = new AutoReloadableDataset(loader, null, false);
	}

	if (loader.getMapping().configuration().getUseAllOptimizations()) {
		log.info("Fast mode (all optimizations)");
	} else {
		log.info("Safe mode (launch using --fast to use all optimizations)");
	}

	// Set up a custom DescribeHandler that calls out to
	// {@link ResourceDescriber}
	DescribeHandlerRegistry.get().clear();
	DescribeHandlerRegistry.get().add(new DescribeHandlerFactory() {
		public DescribeHandler create() {
			return new DescribeHandler() {
				private BulkUpdateHandler adder;

				public void start(Model accumulateResultModel,
						Context qContext) {
					adder = accumulateResultModel.getGraph()
							.getBulkUpdateHandler();
				}

				public void describe(Resource resource) {
					log.info("DESCRIBE <" + resource + ">");
					boolean outgoingTriplesOnly = isVocabularyResource(resource)
							&& !getConfig().getVocabularyIncludeInstances();
					adder.add(new ResourceDescriber(getMapping(), resource
							.asNode(), outgoingTriplesOnly,
							Relation.NO_LIMIT, 
							Math.round(config.getSPARQLTimeout())).description());
				}

				public void finish() {
				}
			};
		}
	});

	Registry.add(RDFServer.ServiceRegistryName,
			createJosekiServiceRegistry());
	
	if (config.getSPARQLTimeout() > 0) {
		ARQ.getContext().set(ARQ.queryTimeout, config.getSPARQLTimeout() * 1000);
	}
	
	startupError = false;
}