From.java

/*******************************************************************************
 * Copyright (c) 2018 Eclipse RDF4J contributors.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Distribution License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 *******************************************************************************/

package org.eclipse.rdf4j.sparqlbuilder.core;

import static org.eclipse.rdf4j.sparqlbuilder.rdf.Rdf.iri;

import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.sparqlbuilder.rdf.Iri;

/**
 * A SPARQL Dataset specifier.
 *
 * @see <a href="http://www.w3.org/TR/2013/REC-sparql11-query-20130321/#specifyingDataset"> Specifying RDF Datasets</a>
 */
public class From implements QueryElement {
	private static final String FROM = "FROM";
	private static final String NAMED = "NAMED";
	private final Iri iri;
	private final boolean isNamed;

	From(Iri iri) {
		this(iri, false);
	}

	From(Iri iri, boolean isNamed) {
		this.iri = iri;
		this.isNamed = isNamed;
	}

	From(IRI iri) {
		this(iri, false);
	}

	From(IRI iri, boolean isNamed) {
		this(iri(iri), isNamed);
	}

	@Override
	public String getQueryString() {
		StringBuilder fromClause = new StringBuilder();

		fromClause.append(FROM).append(" ");
		if (isNamed) {
			fromClause.append(NAMED).append(" ");
		}
		fromClause.append(iri.getQueryString());

		return fromClause.toString();
	}
}