I just completed the code for supporting parameter direction modifiers. When this feature makes into the next build, modelers will be able to choose for named parameters any of the standard parameter direction kinds: out, inout, or (the default) in. By the way, the syntax for specifying return types remains the same. Here is an example:
operation op1(in p1 : String, out p2 : String);
Java developers might consider this feature unnecessary as there is only one way of passing parameters in Java, but for distributed applications (such as those using CORBA or web services) these modifiers are quite relevant.
The corresponding support for rendering operation parameter direction kind modifiers has been added to the TextUML model viewer (decompiler) and EclipseGraphviz graphical rendering component.
This is the first new feature since version 1.0 was released. The impact of implementing it was quite minimal to the code base, so I am looking forward to implementing the next notation feature. The question is: what feature? Any suggestions?