miningfilefilter.java

一个数据挖掘软件ALPHAMINERR的整个过程的JAVA版源代码

/*
 *    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.
 */

/**
 * Title: XELOPES Data Mining Library
 * Description: The XELOPES library is an open platform-independent and data-source-independent library for Embedded Data Mining.
 * Copyright: Copyright (c) 2002 Prudential Systems Software GmbH
 * Company: ZSoft (www.zsoft.ru), Prudsys (www.prudsys.com)
 * @author Valentine Stepanenko ([e-mail])
 * @version 1.0
 */

package com.prudsys.pdm.Transform.Filter;

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

import javax.swing.filechooser.FileFilter;

public class MiningFileFilter
    extends FileFilter {

  private static String TYPE_UNKNOWN = "Type Unknown";
  private static String HIDDEN_FILE = "Hidden File";

  private Hashtable filters = null;
  private String description = null;
  private String fullDescription = null;
  private boolean useExtensionsInDescription = true;

  /**
   * Creates a file filter. If no filters are added, then all
   * files are accepted.
   */
  public MiningFileFilter() {
    this.filters = new Hashtable();
  }

  /**
   * Creates a file filter that accepts files with the given extension.
   * Example: new LogFileFileFilter("jpg");
   *
   */
  public MiningFileFilter(String extension) {
    this(extension, null);
  }

  /**
   * Creates a file filter that accepts the given file type.
   * Example: new LogFileFileFilter("jpg", "JPEG Image Images");
   *
   * Note that the "." before the extension is not needed. If
   * provided, it will be ignored.
   *
   */
  public MiningFileFilter(String extension, String description) {
    this();
    if (extension != null) {
      addExtension(extension);
    }
    if (description != null) {
      setDescription(description);
    }
  }

  /**
   * Creates a file filter from the given string array.
   * Example: new LogFileFileFilter(String {"gif", "jpg"});
   *
   * Note that the "." before the extension is not needed adn
   * will be ignored.
   *
   */
  public MiningFileFilter(String[] filters) {
    this(filters, null);
  }

  /**
   * Creates a file filter from the given string array and description.
       * Example: new LogFileFileFilter(String {"gif", "jpg"}, "Gif and JPG Images");
   *
   * Note that the "." before the extension is not needed and will be ignored.
   *
   */
  public MiningFileFilter(String[] filters, String description) {
    this();
    for (int i = 0; i < filters.length; i++) {
      // add filters one by one
      addExtension(filters[i]);
    }
    if (description != null) {
      setDescription(description);
    }
  }

  /**
   * Return true if this file should be shown in the directory pane,
   * false if it shouldn't.
   *
   * Files that begin with "." are ignored.
   *
   */
  public boolean accept(File f) {
    if (f != null) {
      if (f.isDirectory()) {
        return true;
      }
      String extension = getExtension(f);
      if (extension != null && filters.get(getExtension(f)) != null) {
        return true;
      }
      ;
    }
    return false;
  }

  /**
   * Return the extension portion of the file's name .
   *
   */
  public String getExtension(File f) {
    if (f != null) {
      String filename = f.getName();
      int i = filename.lastIndexOf('.');
      if (i > 0 && i < filename.length() - 1) {
        return filename.substring(i + 1).toLowerCase();
      }
      ;
    }
    return null;
  }

  /**
   * Adds a filetype "dot" extension to filter against.
   *
   * For example: the following code will create a filter that filters
   * out all files except those that end in ".jpg" and ".tif":
   *
   *   LogFileFileFilter filter = new LogFileFileFilter();
   *   filter.addExtension("jpg");
   *   filter.addExtension("tif");
   *
   * Note that the "." before the extension is not needed and will be ignored.
   */
  public void addExtension(String extension) {
    if (filters == null) {
      filters = new Hashtable(5);
    }
    filters.put(extension.toLowerCase(), this);
    fullDescription = null;
  }

  /**
   * Returns the human readable description of this filter. For
   * example: "JPEG and GIF Image Files (*.jpg, *.gif)"
   *
   */
  public String getDescription() {
    if (fullDescription == null) {
      if (description == null || isExtensionListInDescription()) {
        fullDescription = description == null ? "(" : description + " (";
        // build the description from the extension list
        Enumeration extensions = filters.keys();
        if (extensions != null) {
          fullDescription += "." + (String) extensions.nextElement();
          while (extensions.hasMoreElements()) {
            fullDescription += ", " + (String) extensions.nextElement();
          }
        }
        fullDescription += ")";
      }
      else {
        fullDescription = description;
      }
    }
    return fullDescription;
  }

  /**
   * Sets the human readable description of this filter. For
   * example: filter.setDescription("Gif and JPG Images");
   *
   */
  public void setDescription(String description) {
    this.description = description;
    fullDescription = null;
  }

  /**
   * Determines whether the extension list (.jpg, .gif, etc) should
   * show up in the human readable description.
   *
   * Only relevent if a description was provided in the constructor
   * or using setDescription();
   *
   */
  public void setExtensionListInDescription(boolean b) {
    useExtensionsInDescription = b;
    fullDescription = null;
  }

  /**
   * Returns whether the extension list (.jpg, .gif, etc) should
   * show up in the human readable description.
   *
   * Only relevent if a description was provided in the constructor
   * or using setDescription();
   *
   */
  public boolean isExtensionListInDescription() {
    return useExtensionsInDescription;
  }
}