Develop Reference

Android, SimpleDateFormat not working

I'm trying to parse time only but the app code includes the date and the year.
here is my code:
simpleDateFormat2 = new SimpleDateFormat("HH:mm");
int h = Integer.parseInt(traffic.alarmClocks.get(0).get(ApplicationConstants.HOUR));
int m = Integer.parseInt(traffic.alarmClocks.get(0).get(ApplicationConstants.MINUTE));
String datex2 = h + ":" + m;
Date storedalarm = simpleDateFormat2.parse(datex2);
output of the datex2 is : 4:56
Output of StoredAlarm is this: http://imgur.com/a/UVpbh
The output of the datex2 is correct, but I need to make it into date because I am going to use it to compare times.

you just need to compare times you could very easily combine hours and minutes this way:
int time = hours * 60 + minutes;
then you could just compare 2 integers.
or if you really want a Date object, you could initialize it with year, month and date to 0, and just pass hours and minutes
Date storedalarm = new Date(0, 0, 0, h, m);
in order to show just hours and minutes from your Date object you can use the same SimpleDateFormat you instantiated before
String formattedDate = simpleDateFormat2.format(storedalarm);

Same Milliseconds values coming for different dates

I store my values in database by converting the date value in milliseconds,so to get the latest date on top by using order by desc query. The order is coming as required but if i enter date 02/01/2016 and 01/30/2016 both are storing same milliseconds value.
String date = "02/01/2016";
String month = date.substring(0, 2);
String day = date.substring(3, 5);
String year = date.substring(6, 10);
Calendar c1 = Calendar.getInstance();
c1.set(Integer.parseInt(year), Integer.parseInt(month), Integer.parseInt(day));
long left = c1.getTimeInMillis();
After debugging i got the following milliseconds values
02/01/2016----61414914600000
and 01/30/2016----61414914600000
Anybody knows why this happening?

Using SimpleDateFormat value I am getting different milliseconds value:
Date date;
String dtStart = "02/01/2016";
SimpleDateFormat format = new SimpleDateFormat("MM/dd/yyyy");
try {
date = format.parse(dtStart);
long timeMills=date.getTime();
System.out.println("Date ->" + date);
} catch (Exception e) {
e.printStackTrace();
}

I ran your initial code and it functions almost as expected. A few points:
You mention millisecond 61414914600000. That's not correct because it's 1900 years into the future:
http://currentmillis.com/?61414914600000
I'm pretty sure you got that number from a Date object, not from a Calendar: http://docs.oracle.com/javase/6/docs/api/java/util/Date.html#Date(int, int, int)
As Mat said the month is zero-based for Calendar and the line where you call the setter should subtract 1:
c1.set(Integer.parseInt(year), Integer.parseInt(month) - 1, Integer.parseInt(day));
You answered your own question with another snippet of code but Date is deprecated, Calendar should be used instead. Your original code in the initial post was essentially correct (except the zero-based month). You should make sure that you know where your output is coming from and / or that you don't forget to build the code before running it.

Android Timezone Ids are not matching with System Timezone Ids issue

I am working on timezones concept in Android.
I want to change the timezone of the Android tablet by taking the timezone from the App Variable in the application. I am getting the System TimeZones as the variable value i.e like
Dateline Standard Time
UTC-11
Samoa Standard Time
Hawaiian Standard Time
Alaskan Standard Time
Pacific Standard Time (Mexico)
Pacific Standard Time
US Mountain Standard Time
Mountain Standard Time (Mexico)
Mountain Standard Time
Central America Standard Time
Central Standard Time
Central Standard Time (Mexico)
Canada Central Standard Time
SA Pacific Standard Time
From Android case, I am getting Timezone Id's like
Africa/Harare
Africa/Johannesburg
Africa/Kigali
Africa/Lubumbashi
Africa/Lusaka
Africa/Maputo
Africa/Maseru
Africa/Mbabane
Africa/Tripoli
Asia/Amman
Asia/Beirut
Asia/Istanbul
Asia/Jerusalem
Asia/Nicosia
Asia/Tel_Aviv
CAT
EET
Egypt
Etc/GMT-2
Europe/Chisinau
Europe/Helsinki
and my code is
if (mCalendar != null) {
mCalendar = Calendar.getInstance();
}
else
{
String[] allTimeZones = TimeZone.getAvailableIDs();
Arrays.sort(allTimeZones);
for (int i = 0; i < allTimeZones.length; i++) {
System.out.println(allTimeZones[i]);
}
TimeZone tz = TimeZone.getTimeZone(String.valueOf(Jordan Standard Time));
mCalendar = Calendar.getInstance(tz);
String name = tz.getID();
System.out.println("TimeZone "+tz.getDisplayName(false, TimeZone.SHORT)+" Timezon id :: " + name);
}
As 'Jordan Standard Time' is variable from application is not like Timezone of tablet available Id's, Timezone is not changing.
If I replace the Timezone with 'Africa/Tripoli' manually, the timezone is replacing with this one.
My issue now is I would like to convert the system timezones to Tablet Timezone Ids and display it in Android Application.

plz use this function that is display GMT Time display if you change timezone from you android phone.
public static String GetDateForGMTDate(String dateString) {
SimpleDateFormat formatter = new SimpleDateFormat(
"yyyy-mm-dd");
SimpleDateFormat formatter1 = new SimpleDateFormat(
"yyyy-mm-dd");
Date date = null;
try {
date = formatter.parse(dateString);
System.out.println(date);
System.out.println(formatter.format(date));
Calendar cal = Calendar.getInstance();
cal.setTime(date);
Log.i("Time zone", "gettime=" + cal.getTime());
cal.add(Calendar.MINUTE, (-1 * getTimeZoneDifference()));
Log.i("Time zone", "after gmt +gettime=" + cal.getTime());
date = cal.getTime();
} catch (ParseException e) {
e.printStackTrace();
}
return formatter1.format(date);
}
public static final int getTimeZoneDifference() {
long currentTime = System.currentTimeMillis();
int gmtcurrentOffset = TimeZone.getDefault().getOffset(currentTime);
int gmtOffset = TimeZone.getTimeZone("GMT").getOffset(currentTime);
int minuteDifference = (((gmtOffset - gmtcurrentOffset) / 1000) / 60);
return minuteDifference;
}
use 1st function and pass any date with yyy-mm-dd formate as a string. and that function will return gmt formate real date-time.
i already use it.
its working fine.i hope its useful to you.

Determining if a time is between two other times

I am trying to take hours that I've parsed using SimpleDateFormat and determining whether or not the current time is between the two sets of hours. Basically, given a place's hours, I'm trying to determine if it is currently open our closed.
I am getting the current time by doing the following:
SimpleDateFormat sdf2 = new SimpleDateFormat("kk:mm");
Calendar now = Calendar.getInstance();
int hour = now.get(Calendar.HOUR);
int minute = now.get(Calendar.MINUTE);
String currentHour = Integer.toString(hour);
String currentMinute = Integer.toString(minute);
String timeNow = currentHour + ":" + currentMinute;
Date timeRightNow = sdf2.parse(timeNow);
Then, I determine whether timeRightNow is between the opening and closing times, I am doing the following:
if (timeOpen.before(timeRightNow) && timeClose.after(timeRightNow)) {
openStatus = "open!";
} else {
openStatus = "closed.";
}
Both timeOpen and timeClose are found by parsing a String using sdf2 in the exact same way as timeRightNow is found.
Every time that this runs, it sets openStatus to "closed." even when the current time is between the open and close times. Can anyone point me in the right direction to figure out why this is happening?

I changed Calendar.HOUR to Calendar.HOUR_OF_DAY. This resolved the issue.

Formatting Long value to Date String?

I am working on an application in which I have to convert a long value to a Date string and display. To achieve the purpose I am using following function, but it is returning me the date from 70's and 80's obviously not appropriate. I am using the following finction:
public static String convertDateFromLongToCompleteString(long date) {
Date d = new Date(date * 1000);
SimpleDateFormat dateformat = new SimpleDateFormat("dd/MM/yyyy hh:mm a");
String formattedDateFromLong = dateformat.format(d);
return formattedDateFromLong;
}
The long value is just simply System.currentTimeMillis() and when I have to show it to the user, I have to format that for which I am using above function. I have checked system and device dates, their zones and time, everything is just fine. Please update that why is this issue appearing and how can I get the exact date. Thanks!
Edit
I have also tried withoout multiplication with 1000, it gives me time and date from 1970.

If your long date is simply System.currentTimeMillis(), then multiplication with 1000 is not required.
Date d = new Date(date);

Replace Date d = new Date(date * 1000); with Date d = new Date(date);

In case you're using the above method only with System.currentTimeMillis(), you can call Date constructor without any parameters, it will give you the Date object that refers to the current date and time. This will be an easier way to solve your problem. Hope this helps.