
DayPilot Pro includes a Java Gantt chart web control. It display a timeline for a hierarchy of tasks and milestones.
Online demo:
Documentation:
Features:
- Hierarchy of tasks
 - Milestones
 - Task groups (parent tasks)
 - Flexible scale (from minutes to years)
 - Drag and drop support (task moving, resizing; hierarchy changes)
 - Dependencies (task links) - finish-to-start, finish-to-finish, start-to-start, start-to-finish
 - Integrated task creating (last row)
 - Columns with additional task data (id, dependencies, duration...)
 - HTML5 support
 - Mobile/touch devices support
 - Server-side (Java) integration
 - Client-side API (JavaScript)