This page contains information on how to open SignServer in different IDEs:
Open the Maven projects directly in the IDE.
The latest NetBeans IDE (currently 8.2) is recommended with one exception:
The SignServer AdminGUI is implemented using the Swing Application Framework (JSR 296) and requires NetBeans IDE 7.0.x to allow GUI changes. Since JSR 296 didn't make it into the JDK, support for it was dropped in later versions of the IDE.
Define the top-level project, SignServer, as the main project open in the IDE by right-clicking it and and selecting Set as Main Project. This way hitting F6 will be the same as running ant deploy.
The downside is that F11 now maps to Build Main project and it's not convenient to rebuild everything if only working on a small number of modules. To only build the selected project (or the project belonging to the current open file), the shortcut can be redefined to Build project.
When deploying from within the IDE, specify the environment variable APPSRV_HOME to let the script know where to deploy to.
Each SignServer subproject is a Maven project. Import it in Eclipse like any other Maven project.