AspectJ capture button clicked - button

Question

I want to know whether how to capture the button clicked with AspectJ and get its parameter (eg. button name). I think for having more generalized capturing with AspectJ, it shoudl be used MouseListener so it can capture other UI elements in general!
Example:
In a GUI example I have defined 2 buttons that take some actions
public JButton btn1 = new JButton("Test1");
public JButton btn2 = new JButton("Test2");
btn1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//take some actions
}
}
btn2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//take some actions
}
}
How to capture these buttons with AspectJ, and get their parameters (eg. name)?

Answer 1

It is possible. I have provided two examples. The first that prints out for every JButton that has an ActionListener. The other example only prints out if a specific buttons is clicked.
Prints the text for every JButton clicked with an ActionListener:
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent)")
public void buttonPointcut(ActionEvent actionEvent) {}
#Before("buttonPointcut(actionEvent)")
public void beforeButtonPointcut(ActionEvent actionEvent) {
if (actionEvent.getSource() instanceof JButton) {
JButton clickedButton = (JButton) actionEvent.getSource();
System.out.println("Button name: " + clickedButton.getText());
}
}
Prints the text for a specific JButton:
public static JButton j1;
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent) && if()")
public static boolean button1Pointcut(ActionEvent actionEvent) {
return (actionEvent.getSource() == j1);
}
#Before("button1Pointcut(actionEvent)")
public void beforeButton1Pointcut(ActionEvent actionEvent) {
// logic before the actionPerformed() method is executed for the j1 button..
}
UPDATED:
You can do this in many different ways. For example add your buttons to the aspect directly. But I prefere to use a enum object between (ButtonManager in this case), so the code does not know about the aspect. And since the ButtonManager is an enum object, it is easy for the aspect to retrieve values from it.
I just tested it with a Swing button class from Oracle and it works. In the Swing class:
b1 = new JButton("Disable middle button", leftButtonIcon);
ButtonManager.addJButton(b1);
AspectJ is extremely powerful when it comes to manipulating classes, but it can not weave advises into specific objects since objects is not created at the time of weaving. So you can only work with objects at runtime and that is why I have added the addJButton(..) method above. That enables the aspect to check the advised button against a list of registered buttons.
The ButtonManager class:
public enum ButtonManager {
;
private static Collection<JButton> buttonList = new LinkedList<JButton>();
public static void addJButton(JButton jButton) {
buttonList.add(jButton);
}
public static Collection<JButton> getButtonList() {
return buttonList;
}
}
Modified pointcut and advice to only print the name of the buttons registered in the ButtonManager:
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent) && if()")
public static boolean buttonListPointcut(ActionEvent actionEvent) {
Collection<JButton> buttonList = ButtonManager.getButtonList();
JButton registeredButton = null;
for (JButton jButton : buttonList) {
if (actionEvent.getSource() == jButton) {
registeredButton = jButton;
}
}
return registeredButton != null;
}
#Before("buttonListPointcut(actionEvent)")
public void beforeButtonListPointcut(ActionEvent actionEvent) {
JButton clickedButton = (JButton) actionEvent.getSource();
System.out.println("Registered button name: " + clickedButton.getText());
}
UPDATED 2
Okay, I believe I understand what you want. You want to listen to mouse events. That is possible. The downside is that you have to register all your GUI components that you want to listen for clicks with a mouse listener. It is not enough to register the JPanel of the JFrame with a MouseListener. So if you only have registered an ActionListener for your buttons, you also have to add a mouse listener.
I have created a quick solution that works for me. It only shows that it works. I have not tried to make the solution generic with many different GUI objects. But that should be quite easy to refactor in when you have got the basics to work.
In the Swing class:
private class MouseListener extends MouseInputAdapter {
public void mouseClicked(MouseEvent e) {}
}
In the init method of the Swing class:
MouseListener myListener = new MouseListener();
btn1.addMouseListener(myListener);
btn2.addMouseListener(myListener);
In the Aspect class:
#Pointcut("execution(* *.mouseClicked(*)) && args(mouseEvent)")
public void mouseEventPointcut(MouseEvent mouseEvent) {}
#Before("mouseEventPointcut(mouseEvent)")
public void beforeMouseEventPointcut(MouseEvent mouseEvent) {
if (mouseEvent.getSource() instanceof JButton) {
JButton clickedButton = (JButton) mouseEvent.getSource();
System.out.println("aspectJ --> mouseClicked: " + clickedButton.getText());
}
}
This results in the following output in the console:
aspectJ --> mouseClicked: Test1
I hope it helps!