Wednesday, July 6, 2016

Announcing GanttProject 2.8 "Pilsen"

Well, it was supposed to be a maintenance update to GanttProject 2.7.2, but the changes turned out to be big enough to bump the version number rather than maintenance number. The first beta was published today, and we expect the release to be available pretty soon.


The major new feature is actually pretty old one which has been made working. We had so called "additional constraint" called "earliest begin" in task properties for years, and its meaning was pretty vague, mostly because this constraint didn't work.

Task Properties dialog with Additional constraint set to July 14

As of 2.8 this constraint made working and it has clear semantics: task with earliest start constraint set to some date X will be scheduled to start no earlier than X and as close to X as possible, provided that other constraints permit that.

The obvious use of this constraint is to set the earliest date when a task can start. For instance, if task begin date was set on July 5 then changing its earliest start constraint to July 14 will move task to the future (e.g. see issue 1254 which is now fixed)

However, there is another use case which is now possible. If task had start date and earliest start constraint set to July 14, and was moved to some later date because of finish-start dependencies on other tasks then removing the dependencies will move the task back to July 14 (see discussion in issue 1247).

This change may have impact on older projects where earliest start was set but didn't work. When GanttProject 2.8 opens a project file it checks if dates of the tasks remain the same as written in the file after the first run of the scheduler. If some task changes its dates GanttProject will show a report:

Report after the first scheduler run

There is a number of other important bugfixes and translation updates in GanttProject 2.8 [1]. The first beta should be quite stable, as it is really mostly a bugfix update to 2.7.2.


File format has slightly changed -- we removed redundant information about the configuration of task table -- and that's the main reason of the version bump. Files produced by GanttProject 2.7 should open fine in GanttProject 2.8. Files produced by GanttProject 2.8 can be opened by GanttProject 2.7, except that only Name, Begin date and End date columns will be shown in the task table by default, no matter what is written in the project file.

System requirements

GanttProject 2.7 can run on Java 7, but we recommend using Java 8.


Pilsen (Plzeƈ in Czech) is a city in Bohemia region in Czech Republic, known for its excellent beer.


Beta I is available as a platform-independent ZIP distro only (install instructions [3]). You can  download it from Dropbox [2]

[1] The list of issues fixed in GanttProject 2.8:
[2] GanttProject 2.8 beta I packages on Dropbox:
[3] Installing GanttProject from ZIP archive: