There are several file filtering classes and interfaces in Java..
The javax.swing.JFileChooser class is used to create file choosers for selecting files or directories to open or save..
JOptionPane - Simple Dialogs
Here are two useful static methods from javax.swing.JOptionPane..
JOptionPane - More Dialogs
You will learn some more useful static methods from javax.swing.JOptionPane.
The Dialog boxes
There are several ways to build dialog boxes..