UML (Unified Modeling Language) in Software engineering is a universal modeling language for providing users standard way of visualizing the blueprint of a certain system. To clear things for you, we compiled 10 UML open source tools, which are very useful.
ArgoUML
This UML diagramming software is developed using Java and distributed under open source Eclipse Public License. ArgoUML being an application in Java makes it available for any platform Java supports.
ATL
ATL (ATL Transformation Language) – This is a toolkit and a model alteration language. Within the domain of MDE (Model-Driven Engineering), ATL offers ways of producing a collection of target models using source models. ATL is distributed under Eclipse Public License, ATL remains a component of M2M (Eclipse) within EMP (Eclipse Modeling Project).
Dia
This is a free, general-purpose and open source diagramming application. Dia utilizes controlled SDI (Single Document Interface) akin to Inscape and Gimp. This application incorporates modular design that has various shape packages for distinct needs, network diagrams, flowchart, circuit diagrams etc.
Modelio
This open source tool for UML supports BPMN and UML2 standards. The application supports UML2 functions for BPEL and WSDL, XSD, SoaML for supporting service modeling within distributed environments as well as BPMN useful in business process modeling.
NClass
This open source and free tool is useful in creating Unified Modeling Language class diagrams specifically for Java and C# applications. NClass is developed in C# and requires .NET Framework 4.0 or newest Mono version. The application supports just class diagrams of type standard UML.
NetBeans
This IDE is useful in developing mainly through Java but also through other languages particularly, C/C++, HTML5 and PHP. Moreover, it is an application framework useful in Java desktop apps etc.
Papyrus
This UML2 tool is open source and relies on Eclipse; as well, it is licensed under authority of EPL. Papyrus can be exploited as either Eclipse Plugin or standalone tool. The tool supports SysML and Domain Specific Languages.
Umbrello UML Modeller
This free application for UML disagree is natively available to UNIX platforms and MS Windows (as an element in KDE-Windows). Umbrello UML Modeller is incorporated in KDE SC 4 although it functions properly in other programming and desktop environments.