UML modelling Plugin for Eclipse: UML diagrams, source code generation,...
BS Editor: SDE for Eclipse is a UML CASE tool/plug-in tightly integrated with Eclipse. This OO modeling tool supports full software lifecycle - analysis, design, implementation, testing and deployment. This UML software helps you build quality applications FASTER, better and cheaper. You can draw all types of UML Diagrams in Eclipse, reverse engineer Java code to class diagrams, generate Java code and generate documentation.

SDE Features:
+the latest UML support (use case diagram, sequence diagram, collaboration diagram, class diagram, statechart/state diagram, activity diagram, component diagram, deployment diagram, object diagram, package diagram)
+Use case modelling (use case description, scheduling...)
+Textual analysis to identify candidate classes, actors, use cases, flow of events...
+Business Workflow diagram
+CRC Card for finding objects
+Reverse engineering - code to model, code to diagram (Java to UML models, Java to UML diagram)
+Instant Reverse for Java, C++, Dot NET exe/dll, XML, XML Schema, CORBA IDL
+Code Generation - generate code, model to code, diagram to code (UML to code, UML model to Java)
+Incremental round-trip engineering
+Automatic synchronization Between source code and diagrams
+Automatic diagram layout - rearrange shapes and connectors on diagrams in elegant styles
+Import Rational Rose project
+Import XMI/export XMI
+Export diagrams to JPG, PNG, SVG
+Visio Integration - draw UML diagrams with MS Visio stencils
+Report generator for generating UML documentation to HTML or PDF
+Plugin and template
+Version control
+Multilingual support
+More...

Other UML Modeling Tools / UML Plugins:
Java Platform (Mac OS X/Windows/Linux):
+SDE for Eclipse
+SDE for Oracle JDeveloper
+SDE for IBM WebSphere (WSAD)
+SDE for Borland JBuilder
+SDE for IntelliJ IDEA
+SDE for NetBeans
+SDE for Sun ONE
Windows Platform:
+SDE for Microsoft Visual Studio .NET
+More SDE... you can free download SDE for Eclipse (SE) for Java 1.1 Standard Edition now.