commentstripper.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.doc;

import edu.udo.cs.yale.tools.Tools;

import java.io.File;
import java.io.FileReader;
import java.io.Reader;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.FileNotFoundException;

public class CommentStripper {

    private File sourceDir;

    public CommentStripper(File sourceDir) {
	this.sourceDir = sourceDir;
    }

    public String stripClassComment(Class clazz) throws IOException {
	File sourceFile = new File(sourceDir, 
				   clazz.getName().replaceAll("\\.", File.separator) + ".java");
	if (!sourceFile.exists()) 
	    throw new FileNotFoundException("No source file found for class "+clazz.getName()+
					    "; source was expected in '"+sourceFile+"'.");
	StringBuffer comment = null;
	BufferedReader reader = new BufferedReader(new FileReader(sourceFile));
	String line = null;

	final int SCANNING_FOR_COMMENT = 0;
	final int READING_COMMENT      = 1;
	final int FINISHED_COMMENT     = 2;
	int currentState = SCANNING_FOR_COMMENT;
	    
	while ((line = reader.readLine()) != null) {
	    line = line.trim();
	    switch (currentState) {
	    case SCANNING_FOR_COMMENT:
		if (line.startsWith("/**")) {
		    comment = new StringBuffer();
		    line = line.substring("/**".length());
		    currentState = READING_COMMENT;
		} else {
		    break;
		}
	    // ATTENTION (in case someone wants to read this code): there is no break here!
	    case READING_COMMENT:
		int end = line.indexOf("*/");
		if (end != -1) {
		    line = line.substring(0, end);
		    currentState = FINISHED_COMMENT;
		}
		line = stripAsteriks(line);
		if (line.startsWith("@")) continue;
		comment.append(line + " ");
		break;
	    case FINISHED_COMMENT:
		if (line.length() > 0) {
		    int classIndex = line.indexOf("class");
		    int nameIndex  = line.indexOf(Tools.classNameWOPackage(clazz));
		    if ((classIndex != -1) && (nameIndex > classIndex+"class".length())) {
			return comment.toString().trim();
		    } else {
			// this is not what we want
			comment = null;
		    }
		}
		break;
	    }
	}
	reader.close();
	return null;
    }

    private static String stripAsteriks(String string) {
	while (string.startsWith("*")) 
	    string = string.substring(1).trim();
	return string.trim();
    }

}