Microsoft announced the public review of Copilot for Eclipse.

I immediately tried that in one of my Java projects.

Use the “Market Place” to install Copilot in Eclipse:

Once you click install, you must “trust” the contents to be installed:

Once installed and restarted Eclipse, you must authenticate with your GitHub Copilot account by clicking on the Copilot icon in the bottom right:

This will open a dialog with a code you must insert in the opened web page. Note the button to automatically copy the code in the clipboard and open the browser:

In the browser, you’ll have to authenticate in your GitHub account and paste that code (which should be in the clipboard). If everything goes fine, the webpage will tell you that everything is in place to start using Copilot in Eclipse, and Eclipse should show the corresponding success dialog:

I started to do some experiments.

I have this test code where Eclipse shows a warning on the “FileOutputStream” because the resource is not closed. Of course, I know how to solve that: use a try-with-resource block. But let’s ask Copilot.

I opened the file and the Copilot chat (still using the button in the bottom right toolbar):

Here’s what I asked:

I experienced a possible UX design problem here: I didn’t see any answer. I had to enlarge the view to see where Copilot wrote the answer (note in the same part where I wrote the question):

The answer is wrong: that is not the cause of the warning, and that is not the solution.

I tried to be more explicit in the question, detailing the message of the warning:

OK, this time, the answer is correct!

I tried to use the toolbar button to insert the solution in the editor:

However, instead of replacing the interested part, it just inserted that code starting from the editor’s cursor: a disaster of course 😉

Instead of manually copying and pasting the solution, I experimented with Copilot code completion. As I said, I know that I must use a try-with-resource. I converted the lambda expression into a block and typed “try (“. The grey code is suggested by Copilot:

I don’t know whether this is due to the selected solution in the chat or to my previous question, but the proposed code is correct! Press TAB to accept that. Then, I manually removed the duplicate original line. Maybe the original line has been used to propose the correct completion.

For the other part in the same file with the same warning, the completion was done in two steps: I started typing as before, accepted the initial partial condition, went on typing some more, and got the rest of the correct completion:

I also tried asking how to move the Maven project to Java 21 by opening the POM and using the chat:

The answer is correct, but honestly, the question was relatively trivial 😉

Unfortunately, Copilot code completion in the POM file does not work well: it tends to interfere with the default content assist in the POM; I haven’t found a way to use that properly.

Other valid key bindings:

• Ctrl + Alt + / to manually trigger Copilot’s code completion;
• Ctrl + Right to accept the next word in a suggestion.

Let’s see for future updates 🙂

In the meantime, I’ll try to experiment with that further.