Convert Long to Date & String to Date

long amal = 11891;
DateFormat df = new SimpleDateFormat("dd/MM/yyyy");

try
{
Date today = df.parse("20/12/2005");
System.out.println("Today = " + df.format(today)+ "*********");
System.out.println( "long = "+ df.format( new Date(amal)) );
} catch (ParseException e)
{
e.printStackTrace();
}