void (@NotNull Project project) { ApplicationManager.getApplication().runWriteAction(() -> { JavaProjectModelModificationService service = JavaProjectModelModificationService.getInstance(project); for (Module module : ModuleManager.getInstance(project).getModules()) { LanguageLevel languageLevel = LanguageLevelUtil.getCustomLanguageLevel(module); if (languageLevel != null && !isLanguageLevelAccepted(languageLevel)) { LanguageLevel newLanguageLevel = adjustLanguageLevel(languageLevel); service.changeLanguageLevel(module, newLanguageLevel, false); } } LanguageLevelProjectExtension projectExtension = LanguageLevelProjectExtension.getInstance(project); if (!isLanguageLevelAccepted(projectExtension.getLanguageLevel())) { projectExtension.setLanguageLevel(getHighestAcceptedLevel()); } }); }