Umbrello UML Modeller is a free software UML diagram tool available natively for Unix-like platforms, as well as Microsoft Windows (as part of KDE-Windows). It is part of the KDE SC 4 but works well with other desktops and programming environments.
Umbrello handles all the standard UML diagram types. It can reverse engineer code written in C++, IDL, Pascal/Delphi, Ada, Python, and Java, as well as import XMI files generated by external tools from PHP or Perl code (, ) and export to various programming languages.
Umbrello allows distribution of model contents by exporting to DocBook and XHTML formats. This aids in collaborative development efforts where team members may not have direct access to Umbrello, or in cases where model contents should be published on a web site.
It is released along the kdesdk module of KDE.
Read more about Umbrello UML Modeller: Supported Export Programming Languages