We’ve just released a preview version of the next major BlueJ release, 4.0.0. It’s version 4.0.0preview2, available for download from the main website. There’s several features available in this preview release:
Stride is our blocks-like structured code editor which we added to Greenfoot 3, and we’ve now added it to BlueJ as well. There’s lots of details elsewhere on Stride so I won’t reproduce it all here. There is our guide with a simple text+pictures overview of the editor. We recently noticed that a conference talk we gave at last year’s JavaOne made its way online, so you can watch a video of that on Youtube. And Michael has been making a few short videos about Stride over on his blog, which you can watch. We’ve now included two-way conversion from Stride to Java and Java to Stride, so it’s easy to take your existing Java projects and convert them to Stride to get a good feel for the editor.
We’ve also added Git to BlueJ. People have been asking for Git support for years, but previously we only had Subversion and CVS(!) support. We’ve now added Git, with a fairly simple interface that makes it easy to get started with using Git to version control and share BlueJ projects. We’ve got a draft tutorial online for Git in BlueJ. (And CVS support has now been removed.)
Another major change is in the error highlighting. Previously, BlueJ would only show an error when you hit the compile button, and then only one. That’s now changed to match the behaviour of most Java IDEs: errors are shown as a red underline as you write the code, and if there are several errors, they are all highlighted. It will be interesting, once the full release is out, to look at our Blackbox data and see what effect this change has (if any) on programming behaviour in BlueJ.
The last change is one of the most time-consuming but least catchy. We’ve rewritten large parts of BlueJ’s interface (from using Swing to using JavaFX, the newer Java GUI toolkit). Along the way we’ve improved various features, which I’ll talk more about another time. Probably the most noticeable change is that we now support tabbed editors (you can see the tabs in the pictures above), with multiple editor tabs in one window, rather than always having a new window for each editor (another oft-requested feature).
It’s called a preview release because we know it’s not quite finished: there’s still a bit of GUI to improve, some small bugs to iron out and so on. But we think it’s close enough to let everyone have a play with it. If you spot any issues, let us know: in the comments here, by email to email@example.com, or on the Blueroom teachers site.