As I continue my efforts to organize the content on this site, here is a collection of JOptionPane tutorials and examples.
I think the JOptionPane showMessageDialog is used more often than any other JOptionPane dialog, so I've tried to include many different examples of it:
Just one JOptionPane showConfirmDialog tutorial/example so far:
Just one JOptionPane showOptionDialog tutorial/example so far:
Just one JOptionPane showInputDialog tutorial/example so far:
(That last link is only loosely related to the JOptionPane but I thought I would share it here anyway.)