About Java Default Method Use Case 1 - Override ActionListener (Show wait cursor when task is running) ...

A Simple Calculator Program which can perform basic addition, subtraction, multiplication, division operation. Java ActionListener is used to notified whenever someone click on the button or menu item ...

When the button is pressed, then the macro is executed. One cool feature in JSR-223 is to allow scripts to implement Java interfaces. For example, we wish to implement the ActionListener interface.