core/play/src/main/java/play/mvc/Results.java
public static Result notFound(JsonNode content, JsonEncoding encoding) {
    return status(NOT_FOUND, content, encoding);
  }
public static Result notFound(JsonNode content, JsonEncoding encoding) {
    return status(NOT_FOUND, content, encoding);
  }
Generates a 404 Not Found result.

@param content the result's body content as a play-json object
@param encoding the encoding into which the json should be encoded
@return the result