javax.swing.JOptionPane.showMessageDialog() 方法

//default title and icon
            JOptionPane.showMessageDialog(frame,
            "Eggs are not supposed to be green.",
            "Message");
            

//custom title, warning icon
            JOptionPane.showMessageDialog(frame,
            "Eggs are not supposed to be green.",
            "Inane warning",
            JOptionPane.WARNING_MESSAGE);
            

//custom title, error icon
            JOptionPane.showMessageDialog(frame,
            "Eggs are not supposed to be green.",
            "Inane error",
            JOptionPane.ERROR_MESSAGE);
            

//custom title, no icon
            JOptionPane.showMessageDialog(frame,
            "Eggs are not supposed to be green.",
            "A plain message",
            JOptionPane.PLAIN_MESSAGE);
            

//custom title, custom icon
            JOptionPane.showMessageDialog(frame,
            "Eggs are not supposed to be green.",
            "Inane custom dialog",
            JOptionPane.INFORMATION_MESSAGE,
            icon);