source: trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/commands/AbstractTrainCommand.java

package de.ugoe.cs.eventbench.commands;

import java.security.InvalidParameterException;
import java.util.Collection;
import java.util.List;

import de.ugoe.cs.eventbench.CommandHelpers;
import de.ugoe.cs.eventbench.SequenceInstanceOf;
import de.ugoe.cs.eventbench.data.Event;
import de.ugoe.cs.eventbench.data.GlobalDataContainer;
import de.ugoe.cs.eventbench.models.TrieBasedModel;
import de.ugoe.cs.util.console.Command;

/**
 * <p>
 * Abstract class for commands to train {@link TrieBasedModel}s.
 * </p>
 * 
 * @author Steffen Herbold
 * @version 1.0
 */
public abstract class AbstractTrainCommand implements Command {

        /**
         * <p>
         * Handling of additional parameters.
         * </p>
         * 
         * @param parameters
         *            same as the parameters passed to {@link #run(List)}.
         * @throws Exception
         *             thrown, if there is an error parsing the parameters
         */
        abstract void handleAdditionalParameters(List<Object> parameters)
                        throws Exception;

        /**
         * <p>
         * Returns a concrete instance of {@link TrieBasedModel} to be trained. This
         * is a factory method.
         * </p>
         * 
         * @return instance of {@link TrieBasedModel}
         */
        abstract TrieBasedModel createModel();

        /**
         * <p>
         * The command is implemented as a template method. The general structure of
         * the command is always the same, only the parameters of the command and
         * the creation of the {@link TrieBasedModel} instance. The former is
         * handled by {@link #handleAdditionalParameters(List)}, the latter by
         * {@link #createModel()}.
         * </p>
         * 
         * @see de.ugoe.cs.util.console.Command#run(java.util.List)
         */
        @SuppressWarnings("unchecked")
        @Override
        public void run(List<Object> parameters) {
                String modelname;
                String sequencesName;

                try {
                        modelname = (String) parameters.get(0);
                        sequencesName = (String) parameters.get(1);
                        handleAdditionalParameters(parameters);
                } catch (Exception e) {
                        throw new InvalidParameterException();
                }

                Object dataObject = GlobalDataContainer.getInstance().getData(
                                sequencesName);
                if (dataObject == null) {
                        CommandHelpers.objectNotFoundMessage(sequencesName);
                        return;
                }
                if (!SequenceInstanceOf.isCollectionOfSequences(dataObject)) {
                        CommandHelpers.objectNotType(sequencesName,
                                        "Collection<List<Event<?>>>");
                        return;
                }
                Collection<List<? extends Event<?>>> sequences = (Collection<List<? extends Event<?>>>) dataObject;

                TrieBasedModel model = createModel();
                model.train(sequences);
                if (GlobalDataContainer.getInstance().addData(modelname, model)) {
                        CommandHelpers.dataOverwritten(modelname);
                }

        }

}