org.eclipse.mdm.nucleus/org.eclipse.mdm.businessobjects/src/main/java/org/eclipse/mdm/businessobjects/boundary/ClassificationService.java

/*******************************************************************************
 * Copyright (c) 2019 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *******************************************************************************/

package org.eclipse.mdm.businessobjects.boundary;

import java.util.Optional;
import java.util.stream.Collectors;

import javax.ejb.Stateless;
import javax.inject.Inject;

import org.eclipse.mdm.api.base.adapter.EntityType;
import org.eclipse.mdm.api.base.adapter.ModelManager;
import org.eclipse.mdm.api.base.query.ComparisonOperator;
import org.eclipse.mdm.api.base.query.Condition;
import org.eclipse.mdm.api.base.query.Filter;
import org.eclipse.mdm.api.base.query.QueryService;
import org.eclipse.mdm.api.base.query.Record;
import org.eclipse.mdm.api.base.query.Result;
import org.eclipse.mdm.api.dflt.EntityManager;
import org.eclipse.mdm.api.dflt.model.Classification;
import org.eclipse.mdm.api.dflt.model.Domain;
import org.eclipse.mdm.api.dflt.model.ProjectDomain;
import org.eclipse.mdm.api.dflt.model.Status;
import org.eclipse.mdm.businessobjects.control.MDMEntityAccessException;
import org.eclipse.mdm.connector.boundary.ConnectorService;

/**
 * @author akn
 *
 */
@Stateless
public class ClassificationService {

	@Inject
	private ConnectorService connectorService;

	public Classification getClassification(String sourceName, Status status, ProjectDomain projectDomain,
			Domain domain) {
		Optional<QueryService> queryService = connectorService.getContextByName(sourceName).getQueryService();
		Optional<ModelManager> modelManager = connectorService.getContextByName(sourceName).getModelManager();

		EntityType entityType = modelManager.get().getEntityType(Classification.class);
		Condition c1 = ComparisonOperator.CASE_INSENSITIVE_EQUAL.create(entityType.getAttribute("ProjectDomain"),
				projectDomain.getID());
		Condition c2 = ComparisonOperator.CASE_INSENSITIVE_EQUAL.create(entityType.getAttribute("Domain"),
				domain.getID());
		Condition c3 = ComparisonOperator.CASE_INSENSITIVE_EQUAL.create(entityType.getAttribute("Status"),
				status.getID());

		java.util.List<Result> fetch = queryService.get().createQuery().selectID(entityType)
				.fetch(Filter.and().addAll(c1, c2, c3));

		java.util.List<String> collect = fetch.stream().map(r -> r.getRecord(entityType)).map(Record::getID)
				.collect(Collectors.toList());

		EntityManager em = this.connectorService.getContextByName(sourceName).getEntityManager()
				.orElseThrow(() -> new MDMEntityAccessException("Entity manager not present!"));

		Classification classification = null;
		if (!collect.isEmpty()) {

			classification = em.load(Classification.class, collect.get(0));
		}

		return classification;
	}

}