public static void ensureDirectory(String... filePaths){
  if (filePaths != null) {
    File file;
    for (    String filePath : filePaths) {
      file=new File(filePath);
      if (file.exists() && !file.isDirectory()) {
        throw new IllegalArgumentException("Given path is not a directory: " + file.getAbsolutePath());
      }
 else       if (!file.exists()) {
        if (!file.mkdirs()) {
          throw new IllegalStateException("Could not create directory: " + file.getAbsolutePath());
        }
      }
    }
  }
}

public static void ensureDirectory ( String ... filePaths ) { if ( filePaths != null ) { File file ; for ( String filePath : filePaths ) { file = new File ( filePath ) ; if ( file . exists ( ) && ! file . isDirectory ( ) ) { throw new IllegalArgumentException ( "Given path is not a directory: " + file . getAbsolutePath ( ) ) ; } else if ( ! file . exists ( ) ) { if ( ! file . mkdirs ( ) ) { throw new IllegalStateException ( "Could not create directory: " + file . getAbsolutePath ( ) ) ; } } } } }
ensures that the directories exist
