Create a Java Date from a String and vise versa

Question

I have a date in Integer format(YYYYMMDD). And a start_time as a String (HH:mm 24 hour system)

Answer 1

You have very many representations of date.

When in doubt, I usually head for getting to unix standard time (milliseconds since 1970) as soon as possible.

In this case it would be to convert the Integer date to a String, read out the four first as a year, two digits as month and the last two as day day, and then do the similar thing for the 24h time, and create a java.util.Date from this like so:

SimpleDateFormat dateParser=new SimpleDateFormat("yyyyMMdd HH:mm"); //please double check the syntax for this guy...
String yyyyMmDd = date.toString();
String fullDate = yyyyMmDd + " " + start_time;
java.util.Date startDate = dateParser.parse(fullDate);
long startTimeInMillis = startDate.getTime();
final long MILLISECONDS_PER_HOUR = 1000*60*60;
long durationInMillis = (long)duration*MILLISECONDS_PER_HOUR;
java.util.Date endDate = new java.util.Date(startTimeInMillis + durationInMillis);

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