package de.ugoe.cs.quest.plugin.mfc;

import de.ugoe.cs.quest.plugin.mfc.guimodel.WindowTree;

/**
 * <p>
 * Base class to define custom message handlers, for messages that shall be handled differently
 * during the parsing of usage logs. It provides dummy implementations for all required methods,
 * such that implementations can only overwrite the parts they actually require and ignore the rest.
 * </p>
 * 
 * @author Steffen Herbold
 * @version 1.0
 */
public class MessageHandler {

    /**
     * <p>
     * during parsing, a tree of GUI elements is created and adapted.
     * This is the reference to it.
     * </p>
     */
    private WindowTree windowTree;

    /**
     * <p>
     * Constructor. Protected to prohibit initialization of the base class itself.
     * </p>
     * 
     * @param windowTree the tree of GUI element specifications to be created and adapted during
     *                   parsing
     */
    protected MessageHandler(WindowTree windowTree) {
        this.windowTree = windowTree;
    }

    /**
     * <p>
     * Called in the startElement() method of the {@link MFCLogParser} when a msg-node begins.
     * </p>
     */
    public void onStartElement() {}

    /**
     * <p>
     * Called by the {@link MFCLogParser} to handle param-nodes.
     * </p>
     * 
     * @param name
     *            name (type) of the parameter
     * @param value
     *            value of the parameter
     */
    public void onParameter(String name, String value) {}

    /**
     * <p>
     * Called in the endElement() method of {@link MFCLogParser} when a msg-node ends.
     * </p>
     */
    public void onEndElement() {}

    /**
     * @return the window tree created and adapted during parsing
     */
    protected WindowTree getWindowTree() {
        return windowTree;
    }
    
}
