title: Android - Firebase ServerValue.TIMESTAMP returns "{.sv=timestamp}"
body: <p>I have to save <strong>ServerValue.TIMESTAMP</strong> in my Database but it must be a string. When I type <code>String.valueOf(ServerValue.TIMESTAMP);</code> or <code>ServerValue.TIMESTAMP.toString();</code> it returs "{.sv=timestamp}". I want <code>"1523084664300"</code> instead of <code>1523084664300</code></p>