Converting String to datefield / Java Microedition

Question

Using J2ME, netbeans 7.2, Developing a mobile app..

I have converted the Datefield value to a String and Now want to put it back to a Datefield. To do this I need to convert the String back to Datefield, I am using the following code but its not happening.

long myFileTime = dateField.getDate().getTime(); // getting current/set date from the datefield into long
         String date = String.valueOf(myFileTime); // converting it to a String to put it back into a different datefield

         Date updatedate= stringToDate(date); // passing the string 'date' to the Method stringToDate() to convert it back to date.
                 dateField1.setDate(updatedate); // updating the date into the new datefield1

public Date stringToDate(String s) 
{
    Calendar c = Calendar.getInstance();

    c.set(Calendar.DAY_OF_MONTH, Integer.parseInt(s.substring(0, 2)));
    c.set(Calendar.MONTH, Integer.parseInt(s.substring(3, 5)) - 1);
    c.set(Calendar.YEAR, Integer.parseInt(s.substring(6, 10)));

    return c.getTime();
}

Answer 1

Since you have mentioned that you have the long myFileTime around, you should be able to use:

Date updatedate=new Date(myFileTime);

To convert back to your date. If only your String is available, you should modify your function to this:

public Date stringToDate(String s){
  Calendar c = Calendar.getInstance();

  c.set(Calendar.DAY_OF_MONTH, Integer.parseInt(s.substring(0, 2)));
  c.set(Calendar.MONTH, Integer.parseInt(s.substring(2, 4))-1 );
  c.set(Calendar.YEAR, Integer.parseInt(s.substring(4, 8)));

  return c.getTime();
}

Note the changed indexes.

In Java SE, you should be able to use the following line, instead of setting each fields separately:

c.setTimeInMillis(Long.parseLong(s));

Since in s you have the dateField.getDate().getTime() that is equal to myFileTime , the number of seconds starting with January 1, 1970, based on your provided code.

Your stringToDate should work only if your string will have the following format: ddMMyyyy . Also note that in this case you should use a SimpleDateFormat to parse, something like:

Date updatedate = new java.text.SimpleDateFormat("ddMMyyyy HH:mm:ss").parse(date);