— Scott McNealy, Sun Microsystems Chairman, President and ceo

getting 
gui
you are here
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import javax.swing.*;
public class SimpleGui1 {
public static void main (String[] args) {
JFrame frame = new JFrame();
JButton button = new JButton(“click me”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(button);
frame.setSize(300,300);
frame.setVisible(true);
}
}
Whoa! That’s a 
Really Big Button.
The button fills all the 
available space in the frame. 
Later we’ll learn to control 
where (and how big) the 
button is on the frame.
Your first GUI: a button on a frame
don’t forget to import this 
swing package
(you can pass the button constructor 
the text you want on the button)
give the frame a size, in pixels
finally, make it visible!! (if you forget 
this step, you won’t see anything when 
you run this code)
add the button to the frame’s 
content pane
Let’s see what happens when we run it: 
%java SimpleGui1
make a frame and a button
this line makes the program quit as soon as you 
close the window (if you leave this out it will 
just sit there on the screen forever)

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chapter 12
That’s not exactly true. When you press the button it shows that 
‘pressed’ or ‘pushed in’ look (which changes depending on the 
platform look and feel, but it always does something to show when 
it’s being pressed).
The real question is, “How do I get the button to do something 
specifi c when the user clicks it?” 
But nothing happens when I click it...
We need two things:
A 
method 
to be called when the user 
clicks (the thing you want to happen as 
a result of the button click).