/*
This file is part of the software framework JStatCom,
a library for building applications for data based analysis.
Copyright (C) 2000-2005 Markus Kraetzig
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA
*/
package com.jstatcom.io;
/*
* @(#)ExampleFileFilter.java 1.8 98/08/26
*
* Copyright 1998 by Sun Microsystems, Inc., 901 San Antonio Road, Palo Alto,
* California, 94303, U.S.A. All rights reserved.
*
* This software is the confidential and proprietary information of Sun
* Microsystems, Inc. ("Confidential Information"). You shall not disclose such
* Confidential Information and shall use it only in accordance with the terms
* of the license agreement you entered into with Sun.
*/
import java.io.File;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import javax.swing.filechooser.FileFilter;
/**
* A convenience implementation of FileFilter that filters out all files except
* for those type extensions that it knows about.
*
* Extensions are of the type ".foo", which is typically found on Windows and
* Unix boxes, but not on Macinthosh. Case is ignored.
*
* Example - create a new filter that filerts out all files but gif and jpg
* image files:
*
* JFileChooser chooser = new JFileChooser(); ExampleFileFilter filter = new
* ExampleFileFilter( new String{"gif", "jpg"}, "JPEG & GIF Images")
* chooser.addChoosableFileFilter(filter); chooser.showOpenDialog(this);
*
* @version 1.8 08/26/98
* @author Jeff Dinkins
*/
public final class ExtensionFileFilter extends FileFilter {
private DataHandlerTypes type = null;
private Map filters = new HashMap();
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.
*
* @see #addExtension
*/
public ExtensionFileFilter() {
}
/**
* Creates a file filter from the given string array. Example: new
* ExampleFileFilter(String {"gif", "jpg"});
*
* Note that the "." before the extension is not needed adn will be ignored.
*
* @see #addExtension
*/
public ExtensionFileFilter(String[] filters) {
this(filters, null);
}
/**
* Creates a file filter from the given string array and description.
* Example: new ExampleFileFilter(String {"gif", "jpg"}, "Gif and JPG
* Images");
*
* Note that the "." before the extension is not needed and will be ignored.
*
* @see #addExtension
*/
public ExtensionFileFilter(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);
}
/**
* Creates a file filter that accepts files with the given extension.
* Example: new ExampleFileFilter("jpg");
*
* @see #addExtension
*/
public ExtensionFileFilter(String extension) {
this(extension, null);
}
/**
* Creates a file filter that accepts the given file type. Example: new
* ExampleFileFilter("jpg", "JPEG Image Images");
*
* Note that the "." before the extension is not needed. If provided, it
* will be ignored.
*
* @see #addExtension
*/
public ExtensionFileFilter(String extension, String description) {
this();
if (extension != null)
addExtension(extension);
if (description != null)
setDescription(description);
}
/**
* Creates a file filter that accepts the given file type. Example: new
* ExampleFileFilter("jpg", "JPEG Image Images");
*
* Note that the "." before the extension is not needed. If provided, it
* will be ignored.
*
* @see #addExtension
*/
public ExtensionFileFilter(String extension, String description,
DataHandlerTypes type) {
this(extension, description);
this.type = type;
}
/**
* Return true if this file should be shown in the directory pane, false if
* it shouldn't.
*
* Files that begin with "." are ignored.
*
* @see #getExtension
*/
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;
}
/**
* 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":
*
* ExampleFileFilter filter = new ExampleFileFilter();
* 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 HashMap(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)"
*
* @see #setDescription
* @see #setExtensionListInDescription
* @see #isExtensionListInDescription
* @see FileFilter#getDescription
*/
public String getDescription() {
if (fullDescription == null) {
if (description == null || isExtensionListInDescription()) {
fullDescription = description == null ? "(" : description
+ " (";
// build the description from the extension list
Iterator extensions = filters.keySet().iterator();
if (extensions != null) {
fullDescription += "." + extensions.next();
while (extensions.hasNext()) {
fullDescription += ", " + extensions.next();
}
}
fullDescription += ")";
} else {
fullDescription = description;
}
}
return fullDescription;
}
/**
* Return the extension portion of the file's name .
*
* @see #getExtension
* @see FileFilter#accept
*/
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;
}
/**
* 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();
*
* @see #getDescription
* @see #setDescription
* @see #setExtensionListInDescription
*/
public boolean isExtensionListInDescription() {
return useExtensionsInDescription;
}
/**
* Sets the human readable description of this filter. For example:
* filter.setDescription("Gif and JPG Images");
*
* @see #setDescription
* @see #setExtensionListInDescription
* @see #isExtensionListInDescription
*/
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();
*
* @see #getDescription
* @see #setDescription
* @see #isExtensionListInDescription
*/
public void setExtensionListInDescription(boolean b) {
useExtensionsInDescription = b;
fullDescription = null;
}
/**
* Gets the handler type or null if none has been set.
*
* @return handler type
*/
public DataHandlerTypes getHandlerType() {
return type;
}
}
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