Sets the data to be sent as json.
mixed $data:
public function setData($data = array()) {
// Encode <, >, ', &, and " for RFC4627-compliant JSON, which may also be embedded into HTML.
$this->data = json_encode($data, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT);
return $this
->update();
}