resultservice.java

一个很好的LIBSVM的JAVA源码。对于要研究和改进SVM算法的学者。可以参考。来自数据挖掘工具YALE工具包。

/*
 *  YALE - Yet Another Learning Environment
 *  Copyright (C) 2001-2004
 *      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.tools;

import edu.udo.cs.yale.operator.ResultObject;
import edu.udo.cs.yale.Yale;
import edu.udo.cs.yale.Experiment;

import java.io.*;
import java.util.*;

/** Some statical methods to write results in a file. The class must be set up properly
 *  before you can use these methods. Therefore the destination file is read from
 *  the global part of the experiment configuration file.
 *
 *  @author  Ingo
 *  @version $Id: ResultService.java,v 2.5 2004/08/27 11:57:45 ingomierswa Exp $
 */
public class ResultService {

    private static PrintStream out;



    /** Without initialization stdout is used.. 
     */
    static {
	out = System.out;
    }


    /** Initializes the ResultService. 
     *  @param filename destination file.
     */
    public static void init(String filename) {
	if (filename == null) {
	    LogService.logMessage("No filename given for result file, using stdout for logging results!", LogService.WARNING);
	    init(System.out);
	} else if (filename.equals("stderr")) {
	    init(System.err);
	} else if (filename.equals("stdout")) {
	    init(System.out);
	} else {
	    PrintStream out;
	    try {
		out = new PrintStream(new FileOutputStream(new File(filename)));
	    } catch (IOException e) {
		LogService.logMessage("Cannot create resultfile '"+filename+"': "+e.getClass()+":"+e.getMessage(), LogService.MAXIMUM);
		LogService.logMessage("using stdout", LogService.MAXIMUM);
		out = System.out;
	    }
	    init(out);
	}
    }

    /** Initializes the ResultService. 
     *  @param outStream stream to write the results to.
     */
    public static void init(PrintStream outStream) {
	ResultService.out = outStream;
    }

    /** Initializes the ResultService. 
     */
    public static void init(Experiment experiment) {
	String filename = experiment.getRootOperator().getParameterAsString("resultfile");
	init(filename);
    }



    /** Closes the stream. */
    public static void close() {
	out.close();
    }


    /** Writes the string in the result file.
     */
    public static void logResult(String result) {
	out.println(getTime() + " " + result);
    }

    /** Writes the result string from the given result object in the result file.
     */
    public static void logResult(ResultObject resultObject) {
	logResult(resultObject.toResultString());
    }



    /** Returns the current date and time as formatted string.
     */
    private static String getTime() {
	GregorianCalendar cal = (GregorianCalendar)GregorianCalendar.getInstance();
	String time =
	    zweistellig(cal.get(GregorianCalendar.DAY_OF_MONTH)) + "." +
	    zweistellig((cal.get(GregorianCalendar.MONTH)+1)) + "." +
	    cal.get(GregorianCalendar.YEAR) + " " +
	    zweistellig(cal.get(GregorianCalendar.HOUR_OF_DAY)) + ":" +
	    zweistellig(cal.get(GregorianCalendar.MINUTE)) + ":" +
	    zweistellig(cal.get(GregorianCalendar.SECOND));
	return time;
    }

    /** Adds a leading zero.
     */
    static String zweistellig(int i) {
	return (i < 10 ? "0" : "") + i;
    } 
}