FileFilter is an abstract class used by JFileChooser
for filtering the set of files shown to the user. See
FileNameExtensionFilter for an implementation that filters using
the file name extension.

A FileFilter
can be set on a JFileChooser to
keep unwanted files from appearing in the directory listing.
For an example implementation of a simple file filter, see
yourJDK/demo/jfc/FileChooserDemo/ExampleFileFilter.java.
For more information and examples see
How to Use File Choosers,
a section in The Java Tutorial.

An implementation of FileFilter that filters using a
specified set of extensions. The extension for a file is the
portion of the file name after the last ".". Files whose name does
not contain a "." have no file name extension. File name extension
comparisons are case insensitive.

The following example creates a
FileNameExtensionFilter that will show jpg files:


FileFilter filter = new FileNameExtensionFilter("JPEG file", "jpg", "jpeg");
JFileChooser fileChooser = ...;
fileChooser.addChoosableFileFilter(filter);

FileSystemView is JFileChooser's gateway to the
file system. Since the JDK1.1 File API doesn't allow
access to such information as root partitions, file type
information, or hidden file bits, this class is designed
to intuit as much OS-specific file system information as
possible.



Java Licensees may want to provide a different implementation of
FileSystemView to better handle a given operating system.

FileView defines an abstract class that can be implemented
to provide the filechooser with UI information for a File.
Each L&F JFileChooserUI object implements this
class to pass back the correct icons and type descriptions specific to
that L&F. For example, the Microsoft Windows L&F returns the
generic Windows icons for directories and generic files.
Additionally, you may want to provide your own FileView to
JFileChooser to return different icons or additional
information using JFileChooser.setFileView(javax.swing.filechooser.FileView).



JFileChooser first looks to see if there is a user defined
FileView, if there is, it gets type information from
there first. If FileView returns null for
any method, JFileChooser then uses the L&F specific
view to get the information.
So, for example, if you provide a FileView class that
returns an Icon for JPG files, and returns null
icons for all other files, the UI's FileView will provide
default icons for all other files.



For an example implementation of a simple file view, see
yourJDK/demo/jfc/FileChooserDemo/ExampleFileView.java.
For more information and examples see
How to Use File Choosers,
a section in The Java Tutorial.