How to get data Y M D to pass into Hashmap in Android?

Question

I would like to get the current date and put into hashmap so I can store it in a database. How do I do that?

For example:

 Map<String, String> map = new HashMap<String, String>();{
 map.put("Speed", speed.gettext.tostring());
 map.put("date",currentdate());

  }

Use `new Date().toString()` to retrieve current date as string (with default format) — Vladimir Petrakovich, Mar 19 '16 at 18:44
hi @Wukash Sorry to add on. What if I got other parameter that is in string. See the edited version. So how do I include the date? — Spotty, Mar 19 '16 at 18:45
You use `ContentValues` to put into a database, not a HashMap — OneCricketeer, Mar 19 '16 at 18:50
@fRoStBiT `Calendar.getInstance().getTime()` is the correct way to get the current time as a Date object — OneCricketeer, Mar 19 '16 at 18:52
@cricket_007 Calendar object is unnecessary here. Creating a Calendar is more expensive — Vladimir Petrakovich, Mar 19 '16 at 19:27
@cricket_007 Hi could you explain why is it more expensive? :) thanks — Spotty, Mar 20 '16 at 03:31
@Spotty Method `Calendar.getInstance()` creates new GregorianCalendar object and initializes all its fields (year, month etc.) with current time. `getTime()` creates new `Date` object based on that calendar's time and then we discarding the `Calendar` instance. But we can just create new `Date` object with current time via `new Date()`. — Vladimir Petrakovich, Mar 20 '16 at 04:39

score 1 · Answer 1 · edited May 23 '17 at 12:23

If you use

Map<String, String>

you have no other choice than format the date as string, see SimpleDateFormat. You can use (Simple)DateFormat's format and parse functions to convert date to string and string to date.

But it is not a nice solution, because there are no date type in sqlite. According to https://www.sqlite.org/datatype3.html you have 3 options to store date(time):

TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.

you can see also: Best way to work with dates in Android SQLite

score 0 · Answer 2 · answered Mar 19 '16 at 18:47

You can extract the Year, month and day as below.

Calendar cal = Calendar.getInstance();
cal.setTime(date);
int year = cal.get(Calendar.YEAR);
int month = cal.get(Calendar.MONTH); // month starts at 0 and not from 1.
int day = cal.get(Calendar.DAY_OF_MONTH);

How to get data Y M D to pass into Hashmap in Android?

2 Answers2