DefinitionComparator.java

/*
 * Copyright (c) 2012 Data Harmonisation Panel
 * 
 * All rights reserved. This program and the accompanying materials are made
 * available under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the License,
 * or (at your option) any later version.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution. If not, see <http://www.gnu.org/licenses/>.
 * 
 * Contributors:
 *     HUMBOLDT EU Integrated Project #030962
 *     Data Harmonisation Panel <http://www.dhpanel.eu>
 */

package eu.esdihumboldt.hale.ui.common.definition.viewer;

import java.util.Comparator;
import java.util.Set;

import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;

import eu.esdihumboldt.hale.common.align.model.EntityDefinition;
import eu.esdihumboldt.hale.common.schema.model.Definition;
import eu.esdihumboldt.hale.common.schema.model.GroupPropertyDefinition;
import eu.esdihumboldt.hale.common.schema.model.PropertyDefinition;
import eu.esdihumboldt.hale.common.schema.model.TypeDefinition;

/**
 * Comparator for {@link Definition}s. Groups group properties and normal
 * properties.
 * 
 * @author Simon Templer
 */
public class DefinitionComparator extends ViewerComparator {

	/**
	 * Default constructor
	 */
	public DefinitionComparator() {
		super(new Comparator<String>() {

			@Override
			public int compare(String o1, String o2) {
				return o1.compareToIgnoreCase(o2);
			}
		});
	}

	/**
	 * @see ViewerComparator#compare(Viewer, Object, Object)
	 */
	@SuppressWarnings("unchecked")
	@Override
	public int compare(Viewer viewer, Object e1, Object e2) {
		int cat1 = category(e1);
		int cat2 = category(e2);

		if (cat1 != cat2) {
			return cat1 - cat2;
		}

		String name1 = getSortName(e1);
		String name2 = getSortName(e2);

		// use the comparator to compare the strings
		return getComparator().compare(name1, name2);
	}

	private String getSortName(Object def) {
		if (def instanceof EntityDefinition) {
			def = ((EntityDefinition) def).getDefinition();
		}

		if (def instanceof Definition<?>) {
			return ((Definition<?>) def).getDisplayName();
		}

		return def.toString();
	}

	/**
	 * @see ViewerComparator#category(Object)
	 */
	@Override
	public int category(Object element) {
		if (element instanceof EntityDefinition) {
			element = ((EntityDefinition) element).getDefinition();
		}

		if (element instanceof TypeDefinition) {
			// types first
			return 0;
		}

		if (element instanceof GroupPropertyDefinition) {
			return 1;
		}
		if (element instanceof PropertyDefinition) {
			return 2;
		}
		// used if instances contain metadata, used in
		// DefinitionInstanceTreeViewer
		if (element instanceof Set) {
			return 3;
		}

		return super.category(element);
	}

}