Changes to dependancy Java classes do not take effect until Main .java file is touched

Question

I had give a lot of search on this.. I have a problem that can be summarized with this code:

item.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {

        JDialog ui = new RandomDialog();
    }
});

item is just a menu Item and RandomDialog is a class that extends JDialog .

Every time I made a change in RandomDialog class, I had to "update" the ui declaration from JDialog to RandomDialog and then vice-versa.

What is the problem?

[EDIT]

I have a JFrame , with a JMenuBar and JMenuItem . One of these Items had a listener like the one above. I want to open a JDialog when that item is pressed. What happens is every time I make a change on the code from the class that represents that JDialog (a separate class that extends JDialog ) that change is not presented unless I change the declaration of the JDialog . So imagine that I have the declaration like this:

JDialog ui = new RandomDialog();

If I make a change, I have to put like this:

RandomDialog ui = new RandomDialog();

And next I have to put again:

JDialog ui = new RandomDialog();

And so on, so on...

Answer 1

By changing JDialog to RandomDialog and then back to JDialog you are not changing the code, but you are changing the timestamp of the file. This causes your build system to rebuild the .class file from the Java file, build .jar file, and then possibly deploy it to a server, depending on how you have it set up.

The cause of the problem is that your build system does not realize that this file (with the JMenuItem ) depends on the other file (with the RandomDialog ) so changes to the RandomDialog are not causing a rebuild to be done.

To solve this, you will need to look at your project structure. You have not described how the code is being built. Usually if you use an IDE, it will let you manage project dependencies.

Answer 2

In NetBeans Clean & Build usually will do the necessary re-build.

Be sure to enable Compile On Save