A module is a discrete unit of functionality that can be run, tested, and debugged independently. Modules includes such things as source code, build scripts, unit tests, deployment descriptors, etc. In the project, each module can use a specific SDK or inherit the SDK defined on the project level (see the SDK section later in this guide). A module can depend on other modules of the project.

Getting the current module

To determine the module in the project in question to which the specified VirtualFile belongs use ModuleUtilCore#findModuleForFile. Use ModuleUtilCore#findModuleForPsiElement to find the module for a given PsiElement.

Accessing module roots

Information about module roots can be accessed via the class ModuleRootManager.java, for example, an instance of ModuleFileIndex.java can be obtained, which is similar to the ProjectFileIndex.java but in the scope of a module.

ModuleRootManager.getInstance(currentModule).getFileIndex()

Checking belonging to a module source root

To check if a virtual file or directory belongs to a module source root, use the ProjectFileIndex.getSourceRootForFile method. This method returns null if the file or directory does not belong to any source root of modules in the project.

VirtualFile moduleSourceRoot = ProjectRootManager.getInstance(project).getFileIndex().getSourceRootForFile(virtualFileOrDirectory);