FlexGanttFX Resource-Scheduling Framework Open Sourced Under AGPL License

FlexGanttFX Now Open Source

Dirk Lemmerman has released FlexGanttFX, a resource-scheduling framework, as open source. This framework is designed for generating Gantt charts and has been under development for 15 years. The decision to open source the library aims to make the code more widely available for use by developers and organizations.

AGPL License Choice

The project utilizes the AGPL license. This licensing choice was made to address project maintenance and is consistent with decisions by other commercially-backed open-source projects, such as iText. The AGPL license includes a clause requiring companies that modify and use the software over a network to make their changes public.

Technical Capabilities

FlexGanttFX operates on JavaFX, enabling its use on both desktop and mobile devices. It features high-performance chart rendering by combining Canvas rendering with standard FX nodes, allowing complex charts to display efficiently. The framework is built on four primitives: rows for resources, activities as time-bounded items, layers for grouping and visibility, and links for dependencies.

The framework models time using java.time.Instant, supporting granular timelines from milliseconds to decades. It incorporates time zones, daylight-saving transitions, weekends, and working hours directly into the model. Various layout options are available, including standard bars, line/area charts, and stacked lines for overlapping activities. Direct manipulation editing is supported with constraint hooks for application-specific rules.

Industry Impact

Gantt charts are widely used in project and resource planning across various industries, including logistics, aviation, healthcare, and software development. The open-sourcing of FlexGanttFX provides a new tool for developers needing to visualize and manage complex project timelines and resource allocations, particularly within the JavaFX ecosystem.