/*
* Rapid Beans Framework: ExampleFileFilter.java
*
* Copyright (C) 2009 Martin Bluemel
*
* Creation Date: 08/01/2007
*
* This program 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 3 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 Lesser General Public License for more details.
* You should have received a copies of the GNU Lesser General Public License and the
* GNU General Public License along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
package org.rapidbeans.presentation.swing;
import java.io.File;
import java.util.Enumeration;
import java.util.Hashtable;
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 1.16 07/26/04
* @author Jeff Dinkins
*/
public final class ExampleFileFilter extends FileFilter {
/**
* filters.
*/
private Hashtable<String, ExampleFileFilter> filters = null;
/**
* description of the files to filter.
*/
private String description = null;
/**
* full description of the files to filter.
*/
private String fullDescription = null;
/**
* if extension shoudl be used.
*/
private boolean useExtensionsInDescription = true;
/**
* Creates a file filter. If no filters are added, then all files are
* accepted.
*
* @see #addExtension
*/
public ExampleFileFilter() {
this.filters = new Hashtable<String, ExampleFileFilter>();
}
/**
* Creates a file filter that accepts files with the given extension.
* Example: new ExampleFileFilter("jpg");
*
* @param extension
* the extension
*
* @see #addExtension
*/
public ExampleFileFilter(final 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.
*
* @param extension
* the file extension to be filtered
* @param descr
* the description of the file extension
*
* @see #addExtension
*/
public ExampleFileFilter(final String extension, final String descr) {
this();
if (extension != null) {
addExtension(extension);
}
if (descr != null) {
setDescription(descr);
}
}
/**
* 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.
*
* @param argFilters
* the filters
*
* @see #addExtension
*/
public ExampleFileFilter(final String[] argFilters) {
this(argFilters, 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.
*
* @param argFilters
* the filters
* @param argDescription
* the description
*
* @see #addExtension
*/
public ExampleFileFilter(final String[] argFilters, final String argDescription) {
this();
for (int i = 0; i < argFilters.length; i++) {
// add filters one by one
addExtension(argFilters[i]);
}
if (argDescription != null) {
setDescription(argDescription);
}
}
/**
* Return true if this file should be shown in the directory pane, false if
* it shouldn't.
*
* @param f
* the file Files that begin with "." are ignored.
* @return if the file can be accepted or not
*
* @see #getExtension
* @see FileFilter#accepts
*/
public boolean accept(final File f) {
if (f != null) {
if (f.isDirectory()) {
return true;
}
String extension = getExtension(f);
if (extension != null && this.filters.get(getExtension(f)) != null) {
return true;
}
}
return false;
}
/**
* @param f
* the file
* @return the extension portion of the file's name .
*
* @see #getExtension
* @see FileFilter#accept
*/
public String getExtension(final 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.
*
* @param extension
* the extension to filter for 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(final String extension) {
if (this.filters == null) {
this.filters = new Hashtable<String, ExampleFileFilter>(5);
}
this.filters.put(extension.toLowerCase(), this);
this.fullDescription = null;
}
/**
* @return 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 (this.fullDescription == null) {
if (this.description == null || isExtensionListInDescription()) {
// this.fullDescription = this.description == null ? "(" :
// description + " (";
if (this.description == null) {
this.fullDescription = "(";
} else {
this.fullDescription = this.description + " (";
}
// build the description from the extension list
Enumeration<String> extensions = this.filters.keys();
if (extensions != null) {
this.fullDescription += "." + (String) extensions.nextElement();
while (extensions.hasMoreElements()) {
this.fullDescription += ", ." + extensions.nextElement();
}
}
this.fullDescription += ")";
} else {
this.fullDescription = this.description;
}
}
return this.fullDescription;
}
/**
* Sets the human readable description of this filter. For example:
* filter.setDescription("Gif and JPG Images");
*
* @param argDescription
* the description of this filter
* @see setDescription
* @see setExtensionListInDescription
* @see isExtensionListInDescription
*/
public void setDescription(final String argDescription) {
this.description = argDescription;
this.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();
*
* @param b
* the new value for property (use) ExtensionsInDescription)
*
* @see getDescription
* @see setDescription
* @see isExtensionListInDescription
*/
public void setExtensionListInDescription(final boolean b) {
this.useExtensionsInDescription = b;
this.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();
*
* @return property (use) ExtensionsInDescription
* @see getDescription
* @see setDescription
* @see setExtensionListInDescription
*/
public boolean isExtensionListInDescription() {
return this.useExtensionsInDescription;
}
}