Java IO.pdf - Nguyen Dang Binh

public void setFileView(fileView)
public FileView getFileView()
Java I/O
The current file view determines how information about files is interpreted and displayed to
the user. For instance, you can use a file view to display names but not extensions, icons for
files, last-modified dates of files, file sizes, and more. In general, the more information you
choose to display in the file chooser, the slower your choosers are to display and the longer it
takes to switch directories.
The JFileChooser class has five methods that return information about a file. These methods
are used to display the list of files from which the user can select:
public String getName(File f)
public String getDescription(File f)
public String getTypeDescription(File f)
public Icon getIcon(File f)
public boolean isTraversable(File f)
Each of these methods delegates its work to the file chooser's internal FileView object. Most
of the time the default file view is enough. However, you can write your own subclass of
FileView that implements all five of these methods, then install it in the file chooser with
setFileView(). The getName() method should return the name of the file to be displayed to
the user. The getDescription() method returns a short description of the file, generally not
shown to the user. getTypeDescription() should return a short description of the general
kind of file, also generally not shown to the user. The getIcon() method returns a
javax.swing.ImageIcon object for the type of file, which is generally shown to the user to
the left of the filename. Finally, isTraversable() should return true for directories the user
can enter; returning false for a directory prevents the user from opening it. Example 13.10 is
a FileView class that describes compressed files.
Example 13.10. CompressedFileView
import java.io.*;
import javax.swing.*;
import javax.swing.filechooser.*;
public class CompressedFileView extends FileView {
ImageIcon zipIcon = new ImageIcon("images/zipIcon.gif");
ImageIcon gzipIcon = new ImageIcon("images/gzipIcon.gif");
ImageIcon deflateIcon = new ImageIcon("images/deflateIcon.gif");
public String getName(File f) {
return f.getName();
}
public String getTypeDescription(File f) {
}
if (f.getName().endsWith(".zip")) return "Zip archive";
if (f.getName().endsWith(".gz")) return "Gzipped file";
if (f.getName().endsWith(".dfl")) return "Deflated file";
return null;
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