how to convert date format in android

To get AM PM and 12 hour date format use hh:mm:ss a as string formatter WHERE hh is for 12 hour format and a is for AM PM format.

Note: HH is for 24 hour and hh is for 12 hour date format

SimpleDateFormat formatter = new SimpleDateFormat("mm/dd/yyyy hh:mm:ss a");
            String newFormat = formatter.format(testDate);

Example

String date = "2011/11/12 16:05:06";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/mm/dd HH:MM:SS");
        Date testDate = null;
        try {
            testDate = sdf.parse(date);
        }catch(Exception ex){
            ex.printStackTrace();
        }
        SimpleDateFormat formatter = new SimpleDateFormat("mm/dd/yyyy hh:mm:ss a");
        String newFormat = formatter.format(testDate);
        System.out.println(".....Date..."+newFormat);

You can use the SimpleDateFormat for the same kinds of any date operations.

SimpleDateFormat sourceFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); 
SimpleDateFormat DesiredFormat = new SimpleDateFormat("MM/dd/yyyy HH:MM:SS a");   
                                                             // 'a' for AM/PM

Date date = sourceFormat.parse("2012/12/31 03:20:20");
String formattedDate = DesiredFormat.format(date.getTime());  
// Now formattedDate have current date/time  
Toast.makeText(this, formattedDate, Toast.LENGTH_SHORT).show();  

just use the Time class. Try something similar to this.

Time time = new Time();
time.set(Long.valueOf(yourTimeString));

If you really need a Date object just try this.

Date date = new Date(Long.parse(yourTimeString));