content: /*
   *    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., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  /*
   * Loader.java
   * Copyright (C) 2005 University of Waikato, Hamilton, New Zealand
   *
   */
  
  package weka.gui;
  
  import java.io.Reader;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.net.URL;
  
  /**
   * This class is for loading resources from a JAR archive.
   *
   * @author FracPete (fracpete at waikato dot ac dot nz)
   * @version $Revision: 1.2 $ 
   */
  
  public class Loader {
    /** the dir to use as prefix if filenames are w/o it, must have a slash
     * at the end (the path separator is a slash!) */
    private String          dir;
    
    /**
     * initializes the object
     */
    public Loader(String dir) {
      this.dir = dir;
    }
    
    /**
     * returns the dir prefix
     */
    public String getDir() {
      return dir;
    }
    
    /**
     * returns the processed filename, i.e. with the dir-prefix if it's
     * missing
     */
    public String processFilename(String filename) {
      if (!filename.startsWith(getDir()))
        filename = getDir() + filename;
      
      return filename;
    }
    
    /**
     * returns a URL for the given filename, can be NULL if it fails
     */
    public static URL getURL(String dir, String filename) {
      Loader         loader;
      
      loader = new Loader(dir);
      return loader.getURL(filename);
    }
    
    /**
     * returns a URL for the given filename, can be NULL if it fails
     */
    public URL getURL(String filename) {
      filename = processFilename(filename);
      return Loader.class.getClassLoader().getResource(filename);
    }
    
    /**
     * returns an InputStream for the given dir and filename, can be NULL if it 
     * fails
     */
    public static InputStream getInputStream(String dir, String filename) {
      Loader         loader;
      
      loader = new Loader(dir);
      return loader.getInputStream(filename);
    }
    
    /**
     * returns an InputStream for the given filename, can be NULL if it fails
     */
    public InputStream getInputStream(String filename) {
      filename = processFilename(filename);
      return Loader.class.getResourceAsStream(filename);
    }
    
    /**
     * returns a Reader for the given filename and dir, can be NULL if it fails
     */
    public static Reader getReader(String dir, String filename) {
      Loader            loader;
      
      loader = new Loader(dir);
      return loader.getReader(filename);
    }
    
    /**
     * returns a Reader for the given filename, can be NULL if it fails
     */
    public Reader getReader(String filename) {
      InputStream          in;
      
      in = getInputStream(filename);
      
      if (in == null)
        return null;
      else
        return new InputStreamReader(in);
    }
  }
  