modelloader.java

著名的开源仿真软件yale

/*
 *  YALE - Yet Another Learning Environment
 *  Copyright (C) 2002, 2003
 *      Simon Fischer, Ralf Klinkenberg, Ingo Mierswa, 
 *          Katharina Morik, Oliver Ritthoff
 *      Artificial Intelligence Unit
 *      Computer Science Department
 *      University of Dortmund
 *      44221 Dortmund,  Germany
 *  email: [e-mail]
 *  web:   http://yale.cs.uni-dortmund.de/
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License as 
 *  published by the Free Software Foundation; either version 2 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
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 *  USA.
 */
package edu.udo.cs.yale.operator;

import edu.udo.cs.yale.operator.parameter.*;
import edu.udo.cs.yale.operator.learner.FileModel;
import edu.udo.cs.yale.operator.learner.Model;
import edu.udo.cs.yale.tools.LogService;

import java.util.List;
import java.io.File;
import java.io.ObjectInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.FileNotFoundException;

/** Reads a {@link edu.udo.cs.yale.operator.learner.Model} from a file that was
 *  generated by a {@link edu.udo.cs.yale.operator.learner.Learner} in a previous
 *  experiment. Every learner has a parameter <var>model_file</var> which can be 
 *  used to specify a file to write the model to.
 *  Once a model is generated, it can be applied several times to newly
 *  acquired data using a model loader, an {@link ExampleSource}, and 
 *  a {@link edu.udo.cs.yale.operator.learner.ModelApplier}.
 * 
 *  @yale.xmlclass ModelLoader
 *  @see edu.udo.cs.yale.operator.learner.Model
 *  @see edu.udo.cs.yale.operator.learner.Learner
 *  @author Simon, Ingo
 *  @version $Id: ModelLoader.java,v 2.4 2003/08/14 10:24:57 fischer Exp $
 */
public class ModelLoader extends Operator {

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


    /** Reads the model from disk and returns it. */
    public IOObject[] apply() throws OperatorException {
	String filename = getParameterAsString("model_file");
	File modelFile = getExperiment().resolveFileName(filename);

	Model model = null;
	try {
	    model = Model.readModel(modelFile);
	} catch (IOException e) {
	    throw new UserError(this, e, 302, new Object[] { filename, e.getMessage() });
	}
	return new IOObject[] { model }; 
    }

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

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

    public List getParameterTypes() {
	List types = super.getParameterTypes();
	types.add(new ParameterTypeFile("model_file", "Filename containing the model to load.", false));
	return types;
    }

}