JavaBuilder for Swing : automatically populating variable references and introducing Javascript-style event handlers

Thanks to the feedback from the previous post, the JavaBuilder now automatically populates the instance variables on the calling Java class with the ones defined in the build file.

However, the area of concern is refactoring of course. if someone changes the variable name on the Java side it becomes out of sync with the name defined in the YAML file and runtime exceptions will occur.

So, as an optional feature to proof the JavaBuilder concept against refactoring, I have introduced an @Name annotation that basically maps the Java instance variable to the name of the control as it was created in the build file.

You can see it in the YAML file (e.g. the "fNameLabel"):
http://code.google.com/p/javabuilders/source/browse/trunk/org.javabuilders.swing/test/org/javabuilders/swing/test/TestFrame.yaml

and in the corresponding Java file:
http://code.google.com/p/javabuilders/source/browse/trunk/org.javabuilders.swing/test/org/javabuilders/swing/test/TestFrame.java

And here it is:

@Name("fNameField") private JTextField  firstNameTextField;

Also, you may have noticed some new things in the YAML file such as:

onFocus
onFocusLost
onKeyPressed
onKeyReleased
onKeyTyped
onAction

This is work in progress to add simple Javascript-style event handlers that will automatically call a corresponding method on the Java side. This reduces the verbosity of code required to create KeyListeners, FocusListeners, MouseListeners, etc.

It's still work in progress, but it will basically find any method on the Java side with the same name as defined in YAML and either zero arguments (e.g. save()) or with one argument that is compatible with the type that generated the event, e.g.

YAML:

- JButton: {name: editButton, text: button.edit, onAction: edit}

Java:

private void edit(JButton sender) {
  JOptionPane.showMessageDialog(this, "Edit invoked from sender with name: " + sender.getName());
}

I plan to enhance it further to automatically recognize event-specific arguments, e.g.:

private void onLastNameKeyPressed(KeyEvent event) {
this.setTitle("Last name key pressed: " + event.getKeyChar());
}

but that's not there yet...coming soon this week, I hope, time permitting. I think the initial concepts of the JavaBuilder are slowly nicely coming together.

P.S. I mentioned this before, but the JavaBuilder concept is NOT Swing-specific. Swing is just the first domain that I am using as a proof of concept. There are some *very* early proofs of a working builder for SWT, but it's just working code to prove this will work across multiple domains. I will only start seriously working on the SWT builder once the Swing one is done.

See some early SWT code samples here:
http://code.google.com/p/javabuilders/source/browse/trunk/org.javabuilders.swt/src/org/javabuilders/swt/
http://code.google.com/p/javabuilders/source/browse/trunk/org.javabuilders.swt/test/org/javabuilders/swt/test/TestShell.yaml

P.S.S. Also, I have settled on the Apache Wicket approach of forcing the Java and YAML files to have the same name and to be in the same package. It's a good idea and will follow the convention over configuration principle.

P.S.S.S. I also plan to add the @Name support for the Java event methods as well, to also proof them in case of refactoring. List of things to do grows by the day...

[EDIT 2008-04-29]
Latest code drop available:
http://javabuilders.googlecode.com/files/javabuilder.swing.0.0.2008-04-29.zip