/*----------------------------------------------------------------------------
Copyright (c)2000 TogetherSoft LLC. Patents pending. All rights reserved.
----------------------------------------------------------------------------*/
package com.togethersoft.modules.genidl;
import java.io.File;
import java.util.Hashtable;
import java.util.Enumeration;
import javax.swing.filechooser.FileFilter;
public class MyFileFilter extends FileFilter {
/**
* Creates a file filter. If no filters are added, then all files are accepted.
* @see #addExtension
*/
public MyFileFilter() {
this((String)null, (String)null);
}
/**
* Creates a file filter that accepts files with the given extension. Example: new ExampleFileFilter("jpg");
* @see #addExtension
*/
public MyFileFilter(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 MyFileFilter(String extension, String aDescription) {
this(new String[] { extension }, aDescription);
}
/**
* 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 MyFileFilter(String[] filterz) {
this(filterz, 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 MyFileFilter(String[] filterz, String aDescription) {
this.filters = new Hashtable(filterz.length);
for (int i = 0; i < filterz.length; i++) {
// add filters one by one
addExtension(filterz[i]);
}
setDescription(aDescription);
}
/**
* 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
* @see FileFilter#accepts
*/
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 .
* @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;
}
/**
* 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 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)"
* @see setDescription
* @see setExtensionListInDescription
* @see isExtensionListInDescription
* @see FileFilter#getDescription
*/
public String getDescription() {
if (fullDescription == null) {
initFullDescription();
}
return fullDescription;
}
/**
* 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 aDescription) {
this.description = aDescription;
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;
}
/**
* 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;
}
private void initFullDescription() {
if (description == null || isExtensionListInDescription()) {
if (description != null) {
fullDescription = description;
}
fullDescription += " (";
// 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;
}
}
private Hashtable filters = null;
private String description = null;
private String fullDescription = null;
private boolean useExtensionsInDescription = true;
}
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