Java IO.pdf - Nguyen Dang Binh

Figure 13.4. The choosable file filters pop-up in a file chooser
Java I/O
Annoyingly, these file filters are not instances of the java.io.FileFilter interface you're
already familiar with. Instead, they're instances of a new abstract class in the
javax.swing.filechooser package. Because of name conflicts with the
java.io.FileFilter interface, any file that imports both packages will have to use the fully
qualified name.
public abstract class javax.swing.filechooser.FileFilter
I would not be surprised to see these replaced by a
java.io.FileFilter objects in a future release.
javax.swing.filechooser.FileFilter is an abstract class instead of
an interface, and it declares a getDescription() method as well as an
accept() method; but other than these minor differences, the two
versions of FileFilter are identical in all important respects. Another
possibility is that the javax.swing.filechooser.FileFilter class
will be renamed javax.swing.filechooser.ChoosableFileFilter
to avoid the annoying name conflict.
This class declares two methods, both abstract:
public abstract boolean accept(File f);
public abstract String getDescription();
The accept() method returns true if the file passes the filter and should be displayed in the
chooser, false if it shouldn't be. Unlike the accept() method java.io.FilenameFilter,
this accept() method is called to filter directories as well as files. Most filters will accept all
directories to allow the user to navigate between directories. The getDescription() method
returns a string describing the filter to be shown to the user in the chooser's pop-up menu; for
example, Text files (*.txt, *.text). Example 13.6 is a simple file filter that only passes
Java source code files:
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