Why do I get com.google.gson.stream.MalformedJsonException with the JsonParser?

Question

Why do I get an com.google.gson.stream.MalformedJsonException? My code:

File configFile = new File("src/main/resources/configs.json");

JsonObject data = (JsonObject) new JsonParser().parse(configFile.toString());

I got the error at the second line. Why? JSON-Lint says that my JSON is valid...

The JSON:

{
  "mongoDb": {
    "srv": true,
    "user": "exampleUser",
    "password": "examplePassword",
    "host": "exampleHost",
    "port": 0
  }
}