RioStatement.java

/*
 * Copyright (C) 2013 lichtflut Forschungs- und Entwicklungsgesellschaft mbH
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.arastreju.sge.io;

import org.arastreju.sge.model.ResourceID;
import org.arastreju.sge.model.nodes.SemanticNode;
import org.arastreju.sge.model.nodes.ValueNode;
import org.openrdf.model.Resource;
import org.openrdf.model.URI;
import org.openrdf.model.Value;
import org.openrdf.model.impl.BNodeImpl;
import org.openrdf.model.impl.LiteralImpl;
import org.openrdf.model.impl.URIImpl;

import java.text.DateFormat;
import java.text.SimpleDateFormat;

/**
 * <p>
 *  Implementation of Sesame RIO statement based on an Arastreju Statement.
 * </p>
 *
 * <p>
 * 	Created Jan 14, 2011
 * </p>
 *
 * @author Oliver Tigges
 */
public class RioStatement implements org.openrdf.model.Statement {
	
	private static DateFormat XML_DATE = new SimpleDateFormat("yyyy-MM-dd");
	
	@SuppressWarnings("unused")
	private static DateFormat XML_TIME = new SimpleDateFormat("HH:mm:ss");

	private final org.arastreju.sge.model.Statement arasStmt;

	// -----------------------------------------------------
	
	/**
	 * Constructor.
	 * @param stmt The Arastreju statement.
	 */
	public RioStatement(final org.arastreju.sge.model.Statement stmt) {
		this.arasStmt = stmt;
	}
	
	// -----------------------------------------------------

	/**
	 * {@inheritDoc}
	 */
	public Resource getContext() {
		return null;
	}

	/**
	 * {@inheritDoc}
	 */
	public Value getObject() {
		final SemanticNode object = arasStmt.getObject();
		if (object.isResourceNode()){
			return new URIImpl(object.asResource().getQualifiedName().toURI());
		} else {
			return createLiteral(object.asValue());
		}
	}

	/**
	 * {@inheritDoc}
	 */
	public URI getPredicate() {
		return new URIImpl(arasStmt.getPredicate().getQualifiedName().toURI());
	}

	/**
	 * {@inheritDoc}
	 */
	public Resource getSubject() {
		final ResourceID subject = arasStmt.getSubject();
		if (subject.asResource().isBlankNode()){
			return new BNodeImpl(subject.getQualifiedName().getSimpleName());
		}
		return new URIImpl(subject.getQualifiedName().toURI());
	}
	
	// ----------------------------------------------------
	
	private Value createLiteral(ValueNode value) {
		switch(value.getDataType()) {
		case DATE:
			return new LiteralImpl(xmlDate(value), new URIImpl("http://www.w3.org/2001/XMLSchema#date"));
		case TIMESTAMP:
			return new LiteralImpl(value.getStringValue(), new URIImpl("http://www.w3.org/2001/XMLSchema#dateTime"));
		case TIME_OF_DAY:
			return new LiteralImpl(value.getStringValue(), new URIImpl("http://www.w3.org/2001/XMLSchema#time"));
		case INTEGER:
			return new LiteralImpl(value.getStringValue(), new URIImpl("http://www.w3.org/2001/XMLSchema#integer"));
		case DECIMAL:
			return new LiteralImpl(value.getStringValue(), new URIImpl("http://www.w3.org/2001/XMLSchema#decimal"));
		
		case STRING:
		default:
			if (value.getLocale() != null) {
				return new LiteralImpl(value.getStringValue(), value.getLocale().getLanguage());
			} else {
				return new LiteralImpl(value.getStringValue());
			}
		}
	}
	
	private String xmlDate(ValueNode value) {
		return XML_DATE.format(value.getTimeValue());
	}
	
}