private void syncExistingAndRemoveObsolete(
     @NotNull IdeModifiableModelsProvider modelsProvider,
     @NotNull Map<Set<String>, LibraryDependencyData> moduleLibrariesToImport,
     @NotNull Map<String, LibraryDependencyData> projectLibrariesToImport,
     @NotNull Set<LibraryDependencyData> toImport,
     @NotNull Map<OrderEntry, OrderAware> orderEntryDataMap,
     @NotNull ModifiableRootModel moduleRootModel,
     boolean hasUnresolvedLibraries) {
   for (OrderEntry entry : moduleRootModel.getOrderEntries()) {
     if (entry instanceof ModuleLibraryOrderEntryImpl) {
       ModuleLibraryOrderEntryImpl moduleLibraryOrderEntry = (ModuleLibraryOrderEntryImpl) entry;
       Library library = moduleLibraryOrderEntry.getLibrary();
       if (library == null) {
         LOG.warn(
             "Skipping module-level library entry because it doesn't have backing Library object. Entry: "
                 + entry);
         continue;
       }
       final VirtualFile[] libraryFiles = library.getFiles(OrderRootType.CLASSES);
       final Set<String> moduleLibraryKey = ContainerUtilRt.newHashSet(libraryFiles.length);
       for (VirtualFile file : libraryFiles) {
         moduleLibraryKey.add(
             ExternalSystemApiUtil.getLocalFileSystemPath(file)
                 + moduleLibraryOrderEntry.getScope().name());
       }
       LibraryDependencyData existing = moduleLibrariesToImport.remove(moduleLibraryKey);
       if (existing == null || !StringUtil.equals(existing.getInternalName(), library.getName())) {
         moduleRootModel.removeOrderEntry(entry);
       } else {
         orderEntryDataMap.put(entry, existing);
         syncExistingLibraryDependency(
             modelsProvider,
             existing,
             library,
             moduleRootModel,
             moduleLibraryOrderEntry.getOwnerModule());
         toImport.remove(existing);
       }
     } else if (entry instanceof LibraryOrderEntry) {
       LibraryOrderEntry libraryOrderEntry = (LibraryOrderEntry) entry;
       String libraryName = libraryOrderEntry.getLibraryName();
       LibraryDependencyData existing =
           projectLibrariesToImport.remove(libraryName + libraryOrderEntry.getScope().name());
       if (existing != null) {
         toImport.remove(existing);
         orderEntryDataMap.put(entry, existing);
       } else if (!hasUnresolvedLibraries) {
         // There is a possible case that a project has been successfully imported from external
         // model and after
         // that network/repo goes down. We don't want to drop existing binary mappings then.
         moduleRootModel.removeOrderEntry(entry);
       }
     }
   }
 }
 private static void removeObsolete(
     @NotNull Map<Set<String>, LibraryDependencyData> moduleLibrariesToImport,
     @NotNull Map<String, LibraryDependencyData> projectLibrariesToImport,
     @NotNull Set<LibraryDependencyData> toImport,
     @NotNull ModifiableRootModel moduleRootModel) {
   Set<String> moduleLibraryKey = ContainerUtilRt.newHashSet();
   for (OrderEntry entry : moduleRootModel.getOrderEntries()) {
     if (entry instanceof ModuleLibraryOrderEntryImpl) {
       Library library = ((ModuleLibraryOrderEntryImpl) entry).getLibrary();
       if (library == null) {
         LOG.warn(
             "Skipping module-level library entry because it doesn't have backing Library object. Entry: "
                 + entry);
         continue;
       }
       moduleLibraryKey.clear();
       for (VirtualFile file : library.getFiles(OrderRootType.CLASSES)) {
         moduleLibraryKey.add(ExternalSystemApiUtil.getLocalFileSystemPath(file));
       }
       LibraryDependencyData existing = moduleLibrariesToImport.remove(moduleLibraryKey);
       if (existing == null) {
         moduleRootModel.removeOrderEntry(entry);
       } else {
         toImport.remove(existing);
       }
     } else if (entry instanceof LibraryOrderEntry) {
       String libraryName = ((LibraryOrderEntry) entry).getLibraryName();
       LibraryDependencyData existing = projectLibrariesToImport.remove(libraryName);
       if (existing == null) {
         moduleRootModel.removeOrderEntry(entry);
       } else {
         toImport.remove(existing);
       }
     }
   }
 }
  @Override
  protected Map<OrderEntry, OrderAware> importData(
      @NotNull final Collection<DataNode<LibraryDependencyData>> nodesToImport,
      @NotNull final Module module,
      @NotNull final IdeModifiableModelsProvider modelsProvider) {
    // The general idea is to import all external project library dependencies and module libraries
    // which don't present at the
    // ide side yet and remove all project library dependencies and module libraries which present
    // at the ide but not at
    // the given collection.
    // The trick is that we should perform module settings modification inside try/finally block
    // against target root model.
    // That means that we need to prepare all necessary data, obtain a model and modify it as
    // necessary.
    final Map<Set<String> /* library paths */, LibraryDependencyData> moduleLibrariesToImport =
        ContainerUtilRt.newHashMap();
    final Map<String /* library name + scope */, LibraryDependencyData> projectLibrariesToImport =
        ContainerUtilRt.newHashMap();
    final Set<LibraryDependencyData> toImport = ContainerUtilRt.newLinkedHashSet();
    final Map<OrderEntry, OrderAware> orderEntryDataMap = ContainerUtil.newLinkedHashMap();

    boolean hasUnresolved = false;
    for (DataNode<LibraryDependencyData> dependencyNode : nodesToImport) {
      LibraryDependencyData dependencyData = dependencyNode.getData();
      LibraryData libraryData = dependencyData.getTarget();
      hasUnresolved |= libraryData.isUnresolved();
      switch (dependencyData.getLevel()) {
        case MODULE:
          Set<String> paths = ContainerUtilRt.newHashSet();
          for (String path : libraryData.getPaths(LibraryPathType.BINARY)) {
            paths.add(
                ExternalSystemApiUtil.toCanonicalPath(path) + dependencyData.getScope().name());
          }
          moduleLibrariesToImport.put(paths, dependencyData);
          toImport.add(dependencyData);
          break;
        case PROJECT:
          projectLibrariesToImport.put(
              libraryData.getInternalName() + dependencyData.getScope().name(), dependencyData);
          toImport.add(dependencyData);
      }
    }

    final boolean finalHasUnresolved = hasUnresolved;

    final ModifiableRootModel modifiableRootModel = modelsProvider.getModifiableRootModel(module);
    LibraryTable moduleLibraryTable = modifiableRootModel.getModuleLibraryTable();
    syncExistingAndRemoveObsolete(
        modelsProvider,
        moduleLibrariesToImport,
        projectLibrariesToImport,
        toImport,
        orderEntryDataMap,
        modifiableRootModel,
        finalHasUnresolved);
    // Import missing library dependencies.
    if (!toImport.isEmpty()) {
      importMissing(
          modelsProvider,
          toImport,
          orderEntryDataMap,
          modifiableRootModel,
          moduleLibraryTable,
          module);
    }
    return orderEntryDataMap;
  }