/*
* 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.io;
import java.io.File;
import java.io.FileInputStream;
import java.io.ObjectInputStream;
import java.util.List;
import weka.classifiers.Classifier;
import weka.core.Instances;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.Model;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.UserError;
import com.rapidminer.operator.learner.weka.WekaClassifier;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeFile;
import com.rapidminer.tools.WekaTools;
/**
* This operator reads in model files which were saved from the Weka toolkit. For models
* learned within RapidMiner please use always the {@link ModelLoader} operator even it the
* used learner was originally a Weka learner.
*
* @author Ingo Mierswa
* @version $Id: WekaModelLoader.java,v 1.7 2008/07/07 07:06:38 ingomierswa Exp $
*/
public class WekaModelLoader extends Operator {
/** The parameter name for "Filename containing the Weka model to load." */
public static final String PARAMETER_MODEL_FILE = "model_file";
public WekaModelLoader(OperatorDescription description) {
super(description);
}
/** Reads the model from disk and returns it. */
public IOObject[] apply() throws OperatorException {
File modelFile = getParameterAsFile(PARAMETER_MODEL_FILE);
Model model = null;
try {
ObjectInputStream in = new ObjectInputStream(new FileInputStream(modelFile));
Classifier classifier = (Classifier)in.readObject();
// try to find some infos about the label
ExampleSet trainingExampleSet = null;
try {
Instances trainingInstances = (Instances)in.readObject();
trainingExampleSet = WekaTools.toRapidMinerExampleSet(trainingInstances);
} catch (Throwable e) {
// no instances were written
log("Problem during reading label information, just try without...");
}
in.close();
model = new WekaClassifier(trainingExampleSet, "Weka Model", classifier);
} catch (Exception e) {
throw new UserError(this, e, 302, new Object[] { modelFile, e.getMessage() });
}
return new IOObject[] { model };
}
public Class<?>[] getInputClasses() {
return new Class[0];
}
public Class<?>[] getOutputClasses() {
return new Class[] { Model.class };
}
public List<ParameterType> getParameterTypes() {
List<ParameterType> types = super.getParameterTypes();
types.add(new ParameterTypeFile(PARAMETER_MODEL_FILE, "Filename containing the Weka model to load.", "model", false));
return types;
}
}