synchronized void clearPointerCaches(String url, VirtualFilePointerListener listener) {
   TreeMap<String, VirtualFilePointerImpl> urlToPointer = myUrlToPointerMaps.get(listener);
   if (urlToPointer == null && ApplicationManager.getApplication().isUnitTestMode()) return;
   assert urlToPointer != null;
   urlToPointer.remove(VfsUtil.urlToPath(url));
   if (urlToPointer.isEmpty()) {
     myUrlToPointerMaps.remove(listener);
   }
 }
    @Override
    public void after(@NotNull final List<? extends VFileEvent> events) {
      cleanContainerCaches();

      if (myUrlsToUpdate == null) {
        return;
      }
      for (String url : myUrlsToUpdate) {
        synchronized (VirtualFilePointerManagerImpl.this) {
          for (TreeMap<String, VirtualFilePointerImpl> urlToPointer : myUrlToPointerMaps.values()) {
            VirtualFilePointerImpl pointer = urlToPointer.remove(url);
            if (pointer != null) {
              String path = VfsUtil.urlToPath(pointer.getUrl());
              urlToPointer.put(path, pointer);
            }
          }
        }
      }

      for (VirtualFilePointer pointer : myPointersToUpdate) {
        ((VirtualFilePointerImpl) pointer).update();
      }

      for (EventDescriptor event : myEvents) {
        event.fireAfter();
      }

      if (!myPointersToUpdate.isEmpty()) {
        VirtualFilePointer[] arr =
            myPointersToUpdate.toArray(new VirtualFilePointer[myPointersToUpdate.size()]);
        myBus.syncPublisher(VirtualFilePointerListener.TOPIC).validityChanged(arr);
      }

      myUrlsToUpdate = null;
      myEvents = null;
      myPointersToUpdate = null;
    }
  @Nullable
  public static String findResourcesCacheDirectory(
      @NotNull Module module, boolean createIfNotFound, @Nullable CompileContext context) {
    final Project project = module.getProject();

    final CompilerProjectExtension extension = CompilerProjectExtension.getInstance(project);
    if (extension == null) {
      if (context != null) {
        context.addMessage(
            CompilerMessageCategory.ERROR,
            "Cannot get compiler settings for project " + project.getName(),
            null,
            -1,
            -1);
      }
      return null;
    }

    final String projectOutputDirUrl = extension.getCompilerOutputUrl();
    if (projectOutputDirUrl == null) {
      if (context != null) {
        context.addMessage(
            CompilerMessageCategory.ERROR,
            "Cannot find output directory for project " + project.getName(),
            null,
            -1,
            -1);
      }
      return null;
    }

    final String pngCacheDirPath =
        VfsUtil.urlToPath(projectOutputDirUrl)
            + '/'
            + RESOURCES_CACHE_DIR_NAME
            + '/'
            + module.getName();
    final String pngCacheDirOsPath = FileUtil.toSystemDependentName(pngCacheDirPath);

    final File pngCacheDir = new File(pngCacheDirOsPath);
    if (pngCacheDir.exists()) {
      if (pngCacheDir.isDirectory()) {
        return pngCacheDirOsPath;
      } else {
        if (context != null) {
          context.addMessage(
              CompilerMessageCategory.ERROR,
              "Cannot create directory " + pngCacheDirOsPath + " because file already exists",
              null,
              -1,
              -1);
        }
        return null;
      }
    }

    if (!createIfNotFound) {
      return null;
    }

    if (!pngCacheDir.mkdirs()) {
      if (context != null) {
        context.addMessage(
            CompilerMessageCategory.ERROR,
            "Cannot create directory " + pngCacheDirOsPath,
            null,
            -1,
            -1);
      }
      return null;
    }

    return pngCacheDirOsPath;
  }