FileType (@NotNull String name, @NotNull String displayName, @NotNull String description, @NotNull String extension, @NotNull Disposable disposable) { FileType myType = new FakeFileType() { @Override public boolean isMyFileType(@NotNull VirtualFile file) { return false; } @Override public @NotNull String getName() { return name; } @Override public @Nls @NotNull String getDisplayName() { return displayName; } @Override public @NotNull @NlsContexts.Label String getDescription() { return description; } }; myFileTypeManager.registerFileType(myType, List.of(new ExtensionFileNameMatcher(extension)), disposable, FileTypeManagerImpl.coreIdeaPluginDescriptor()); return myType; }