JCFileFilter enhances Swing's JFileChooser by allowing you to pass it file extensions. These are the only ones that appear in the file chooser dialog. Extensions are of the type ".txt," ".java," and so on, which are typically found on Windows and Unix platforms, but not on the Macintosh. Case is ignored, so ".txt" is equivalent to ".TXT" as far as the filter is concerned.

The class has versatile constructors and convenience methods for setting both the extensions that are to be filtered and an optional descriptive phrase.

19.2 Constructors


`JCFileFilter()`	The default constructor. This form of the constructor is used to list all file types. To filter files, use the `addExtension()` method. To provide a human-readable description for the extension, use the `setDescription()` method.
`JCFileFilter(String extension)`	Creates a file filter that, initially at least, shows only files of the type whose extension is specified by the String argument. The period (dot) before the extension is optional. More filename extensions may be added using the `addExtension()` method.
`JCFileFilter(String[] filters)`	Creates a file filter for a list of file extensions given as a String array. More may be added using the `addExtension()` method.
`JCFileFilter(String extension, String description)`	Creates a file filter that, initially at least, shows only files of the type whose extension is specified by the String argument. The period (dot) before the extension is optional. More filename extensions may be added using the `addExtension()` method. The human-readable description is retrieved using the `getDescription()` method.

19.3 Methods


`addExtension(String extension)`	Places an additional filename extension in the list of those to filter against. Any filename matching this extension is listed in the file dialog, as well as those that have been added in the constructor. The method may be used multiple times to form a list of extensions to filter against.
`accept(File f)`	This Boolean method is used to determine if the given filename has an extension that is in the list of those to be filtered, that is, to be displayed in the file dialog. Files that begin with "." are ignored, but directories are always shown.
`getExtension(Strings)`	Returns the extension portion of a String.
`set/getDescription()`	Sets or gets the human readable description of this filter. This String is used to preface the list of file extensions that shows up in the file dialog's "Files of type:" combo box. For example, if the filter is set to: `String[] filterTypes = {"gif", "jpg"};` and the description is specified as "`JPEG & GIF Images`", then the combo box displays "*JPEG & GIF Images (.gif, .jpg)*"
`setExtensionListIn Description(` `boolean b)` `isExtensionListIn Description()`	Determines whether the extension list, for example (.jpg, .gif), should show up in the human-readable description. The corresponding Boolean method returns the policy currently in effect.

19.4 Example

The following code snippet sets up a filter for GIF and Java source files. The description, which appears in the file chooser's "Files of type:" combo box along with the extensions themselves, is provided through a parameter passed to the constructor.

Note that you can control whether either part of the description actually appears through the use of setDescription() and setExtensionListInDescription().

19

JCFileFilter

Features of JCFileFilter Constructors Methods Example

19.1 Features of JCFileFilter

19.2 Constructors

19.3 Methods

19.4 Example