The location would depend on 2 factors, whether the configuration is local to the user or shared with the other developers and if you are using the file based (legacy) or the directory based project format.
- File based project, local configuration:
.iwsfile - Directory based project, local configuration:
workspace.xmlfile under.ideadirectory - File based project, shared configuration:
.iprfile - Directory based project, shared configuration:
.xmlfile underrunConfigurationssubdirectory of.ideadirectory or files inside.rundirectory in the project root (you can customize the location of the shared configurations in the latest versions).