@ToString creates additional unneeded field

Using @ToString(includeNames = true) inserts a field called $print$names into the class. This field is neither transient nor static, which causes havoc when using XStream.

Example XStream output:

[
  {
    "name": "み +()[]{}.mp3",
    "size": 690037,
    "outputSize": 0,
    "format": {
      "codec": "mp3",
      "name": "mp3",
      "bitDepth": "s16le",
      "samplingRate": 44100,
      "channels": 2,
      "$print$names": true
    }
  }
]

I don't understand why the field is there in the first place since printNames is a compile-time thing.