The Eclipse Project has posted the first release candidate of Eclipse 3.1, an open source integrated development environment (IDE) for Java. Eclipse also doubles as a base platform for your own applications, an alternative to the AWT and Swing, and a powerful floor wax and dessert topping. The main new features in 3.1 are Ant 1.6, quick fixes for serial version IDs, and support for Java 1.5. Changes since the last milestone release are mostly bug fixes.
I've been using 3.1M7 for a couple of weeks now, and it's a reasonable improvement over 3.0. The one new feature I really don't like is how it automatically hides a lot of your comments and code from you. It thyen further violates user interface principles so basic they often remain unstated to support this code hiding. For instance, if you select all and press delete, it doesn;t actually delete everything in the window. Instead it unhides all the pieces of code it had hidden from you before and you have to press delete a second time. I'm sure there's a checkbox somewhere deep in the preferneces to turn this off but so far I haven't found it. However, this is a minor quibble. Overall, 3.1 is a nice upgrade, especially if you're using Java 1.5.