# Build Order

Often the order in which projects are built is important. For example, if one project requires the Java classes which were defined in another project, the first project must be built after its prerequisite classes have been built. The Workbench allows users to explicitly define the order in which projects are built. Alternatively, users can let the platform compute the build order by interpreting project references as prerequisite relationships. The build order is applied for both building the entire workspace or for a group of projects.

You can change this order on the Build Order preferences page. Initially the Use default builder order option is on, in which case the platform computes the build ordering. Turning off this option enables access to the projects list, the ordering of which can be manipulated. Select projects and use the Up and Down buttons to change the build order. Add and remove projects in the build order using the Add Project and Remove Project buttons. Projects removed from the build order will be built, but they will be built after all projects in the build order are built.

At the bottom of this page, there is a preference for dealing with build orders that contain cycles. Ideally, you should avoid cyclic references between projects. Projects with cycles really logically belong to a single project, and so they should be collapsed into a single project if possible. However, if you absolutely must have cycles, it may take several iterations of the build order to correctly build everything. Changing this preference will alter the maximum number of times the workbench will attempt to iterate over the build order before giving up.

Here is what the Build Order preference page looks like:

Builds
Project menu