Button with Action

Open the Java console to see what happens when you click the button.

This applet illustrates:

Printing on the Java console with System.out.println
Adding "life" to a button via implements ActionListener on the applet, and having a new method called actionPerformed. Notice also the addActionListener in init, for the new button.
The use of this, a Java construct used for refering to the current object, i.e. the one for which you are writing the class. In this example, we are writing a class called myApplet which extends (i.e. is a type of) Applet. Here, this is used to let the button know what object is handling the mouse clicks on the button: it is the current object, our applet when it will be running.
In actionPerformed, notice the use of ActionEvent: this is what will specify the type of event, when it will happen. Then, notice the use of getSource() for the event e: it gets the object that caused the event. In our case, we want to see whether the button was clicked.