public static void checkIfDirectoriesExist(File[] diskDirs) {
    for (File diskDir : diskDirs) {
      if (!diskDir.isDirectory()) {
        if (!diskDir.mkdirs()) {
          throw new GemFireIOException(
              String.format("Unable to create directory : %s",
                  diskDir));
        }
      }
    }
  }
Checks if directories exist, if they don't then create those directories
geode-core/src/main/java/org/apache/geode/internal/cache/DiskStoreFactoryImpl.java