# Editing a build configuration

There are a two ways to edit a build configuration:

1. Double click on the .ajproperties file in the package explorer to open the build configuration file editor.
2. Select or de-select files and folders by using the checboxes in the tree.
3. Save the file.
4. If you edited the active build configuration and automatic building is turned on the project will rebuild.

or

1. In the package explorer select the file(s)/package(s) that you want to exclude or include.
2. Right click then select Exclude from 'active_configuration_name' Configuration or Include in 'active_configuration_name' Configuration if including.
3. The active build configuration will be updated and if automatic building is turned on the project will rebuild.

AspectJ projects
Build configurations

Creating a new build configuration
Switching build configurations
Using build configurations with Ant
.lst file support