Java Excel API JXL - reading cell formated as time

Question

I'm using Java Excel API to read data from Excels sheets in my Android project. I have some columns formated as time like this:

At first I tried read this cell using that code:

String cellContent = cell.getContents();

But as result I got content without hours eg :59:59. After that I tried get this time as seconds. I noticed that when cell data is get as DateCell, Date contents object has negative timestamp. I did some trick and I found value of timestamp for 0:00:00. I set variable with this value as positive (2209161600000L). Now I just add this variable to negative timestamp from cell and devide result by 1000 (milliseconds in second). Everything is fine until 23:59:59. Values above have extra 24 h (24:00:00 is reading as 48:00:00). I saw that Excel keeps this values in different ways.

I can just subtract this 24h but it isnt elegant solution. I want to get content as #:##:## string (which I prefer) or as seconds. Is there any good solution for this issue?

Answer 1

Java Excel API is not developed since 2010 so I change library to Apache POI. Time cell is returned as fraction of 24h.

double fractionOfDay = cell.getNumericCellValue();
long timeInSeconds = Math.round(numericValue * SECONDS_IN_DAY);

Now everything works fine.