TripleReorder.java

/*
 * Copyright 2016 Christoph Böhme
 *
 * 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.culturegraph.mf.triples;

import org.culturegraph.mf.framework.FluxCommand;
import org.culturegraph.mf.framework.ObjectReceiver;
import org.culturegraph.mf.framework.annotations.Description;
import org.culturegraph.mf.framework.annotations.In;
import org.culturegraph.mf.framework.annotations.Out;
import org.culturegraph.mf.framework.helpers.DefaultObjectPipe;
import org.culturegraph.mf.framework.objects.Triple;

/**
 * Shifts subjectTo predicateTo and object around.
 *
 * @author Christoph Böhme
 *
 */
@Description("Shifts subjectTo predicateTo and object around")
@In(Triple.class)
@Out(Triple.class)
@FluxCommand("reorder-triple")
public final class TripleReorder extends
		DefaultObjectPipe<Triple, ObjectReceiver<Triple>> {

	/**
	 * Names of the elements in the triple
	 */
	public enum TripleElement { SUBJECT, PREDICATE, OBJECT };
	// Do not change the item order because the process method
	// uses ordinal().

	private TripleElement subjectFrom = TripleElement.SUBJECT;
	private TripleElement predicateFrom = TripleElement.PREDICATE;
	private TripleElement objectFrom =  TripleElement.OBJECT;

	public TripleElement getSubjectFrom() {
		return subjectFrom;
	}

	public TripleElement getPredicateFrom() {
		return predicateFrom;
	}

	public TripleElement getObjectFrom() {
		return objectFrom;
	}

	public void setSubjectFrom(final TripleElement subjectFrom) {
		this.subjectFrom = subjectFrom;
	}

	public void setPredicateFrom(final TripleElement predicateFrom) {
		this.predicateFrom = predicateFrom;
	}

	public void setObjectFrom(final TripleElement objectFrom) {
		this.objectFrom = objectFrom;
	}

	@Override
	public void process(final Triple triple) {
		final String[] elements = {
				triple.getSubject(),
				triple.getPredicate(),
				triple.getObject(),
		};

		getReceiver().process(new Triple(
				elements[subjectFrom.ordinal()],
				elements[predicateFrom.ordinal()],
				elements[objectFrom.ordinal()]
		));
	}

}