/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2008 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.operator.visualization;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.gui.ExampleVisualizer;
import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.UserError;
import com.rapidminer.tools.ObjectVisualizerService;


/**
 * Remembers the given example set and uses the ids provided by this set
 * for the query for the corresponding example and the creation of a
 * generic example visualizer. This visualizer simply displays the attribute
 * values of the example. Adding this operator is often necessary to 
 * enable the visualization of single examples in the provided plotter
 * components.
 * 
 * @author Ingo Mierswa
 * @version $Id: ExampleVisualizationOperator.java,v 2.11 2006/03/21 15:35:42
 *          ingomierswa Exp $
 */
public class ExampleVisualizationOperator extends Operator {

	private static final Class[] INPUT_CLASSES = { ExampleSet.class };

	private static final Class[] OUTPUT_CLASSES = { ExampleSet.class };

	public ExampleVisualizationOperator(OperatorDescription description) {
		super(description);
	}

	public IOObject[] apply() throws OperatorException {
		ExampleSet exampleSet = getInput(ExampleSet.class);
		Attribute idAttribute = exampleSet.getAttributes().getId();
		if (idAttribute == null) {
			throw new UserError(this, 113, "Id");
		}
		ObjectVisualizerService.addObjectVisualizer(new ExampleVisualizer(exampleSet));

		return new IOObject[] { exampleSet };
	}

	public Class<?>[] getInputClasses() {
		return INPUT_CLASSES;
	}

	public Class<?>[] getOutputClasses() {
		return OUTPUT_CLASSES;
	}
}