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Exception in thread "main" java.text.ParseException: Unparseable date: "1527217399000" [duplicate]

This question already has answers here:
String to Date Conversion mm/dd/yy to YYYY-MM-DD in java [duplicate]
(5 answers)
Converting String to Date using SimpleDateFormat is returning random date [duplicate]
(2 answers)
Closed 4 years ago.
I got some values
"createTime": 1527217399000,
"updateTime": 1527218049000,
"createTime": 1527217399000,
"updateTime": 1527217954000,
But I can not parse them to date format, I'm not sure if there is something wrong with the data format,is there any method to parse them?
SimpleDateFormat format = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );
Long tempTime = 1527217399000L;
Date createDate=format.parse(tempTime.toString());
System.out.println(createDate.toString());
Exception in thread "main" java.text.ParseException: Unparseable date:
"1527217399000"
at java.text.DateFormat.parse(DateFormat.java:366)

If you want to create a Date instance from a long value, use:
Date createDate=new Date(tempTime);
As the Javadoc mentions:
java.util.Date.Date(long date)
Allocates a Date object and initializes it to represent the specified number of milliseconds since the standard base time known as "the epoch", namely January 1, 1970, 00:00:00 GMT.
SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" ) is meant to parse a String of the specified format into a Date (i.e. if you wanted to parse a String such as "2018-05-28 06:12:00" into a Date instance).

Since it's 2018, you really should be making use of the java.time API introduced in Java 8
long createTime = 1527217399000L;
LocalDateTime ldt = Instant.ofEpochMilli(createTime).atZone(ZoneId.systemDefault()).toLocalDateTime();
String format = ldt.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss", Locale.ENGLISH));
System.out.println(format);
Which prints 2018-05-25 13:03:19 (on PC)
And if you don't have Java 8, there's the ThreeTen backport which makes the API available to earlier versions of Java

The old java.util.Date API is notoriously poor and if you want to make clear decisions about what type of date / time you're using - whether it's in a particular timezone, etc. - you should use the java.time API.
Assuming (you'd need to confirm) that these millisecond timestamps are in UTC timezone, you can use code like this to format it as a date/time in your local system timezone.
Long tempTime = 1527217399000L;
Instant instant = Instant.ofEpochMilli(tempTime);
ZonedDateTime dateTime = instant.atZone(ZoneId.systemDefault());
System.out.println(dateTime.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));

How to convert getTime() to 'YYYY-MM-DD HH24:MI:SS' [duplicate]

This question already has answers here:
Convert timestamp in milliseconds to string formatted time in Java
(10 answers)
Closed 5 years ago.
I Have the following code in my application
System.out.println(rec.getDateTrami().getTime());
I need to convert the following format (I suppose that they are seconds)
43782000
29382000
29382000
To a format YYYY-MM-DD HH24:MI:SS, anyone can help to me?

You can make use of the SimpleDateFormat
Example:
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
Date date = new Date();
date.setTime(rec.getDateTrami().getTime());
System.out.println(format.format(date));
Documentation:
SimpleDateFormat,
DateFormat

Use java.time
Best if you can change getDateTrami() to return an OffsetDateTime or ZonedDateTime from java.time. java.time is the modern Java date and time API. It is also known as JSR-310. The code is the same no matter which of the two mentioned types is returned:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
System.out.println(rec.getDateTrami().format(formatter));
This prints a date and time like
2017-12-14 16:52:20
java.time is generally so much nicer to work with than the outmoded Date class and its friends.
If you cannot change the return type
I assume getDateTrami() returns a java.util.Date. Since the Date class is long outmoded, the first thing to do is to convert it to java.time.Instant. From there you perform your further operations:
Date oldfashionedDateObject = rec.getDateTrami();
ZonedDateTime dateTime = oldfashionedDateObject.toInstant()
.atZone(ZoneId.of("Atlantic/Cape_Verde"));
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
System.out.println(dateTime.format(formatter));
The result is similar to the above, of course. I on purpose made explicit in which time zone I want to interpret the point in time. Please substitute your own if it doesn’t happen to be Atlantic/Cape_Verde.
Formatting seconds since the epoch
int seconds = 29_382_000;
ZonedDateTime dateTime = Instant.ofEpochSecond(seconds)
.atZone(ZoneId.of("Atlantic/Cape_Verde"));
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
System.out.println(dateTime.format(formatter));
This snippet prints
1970-12-06 23:40:00
A date in December 1970. If this is incorrect, it is because 29 382 000 didn’t denote seconds since the epoch of January 1, 1970 at midnight in UTC, also known as the Unix epoch. This is by far the most common time to measure seconds from. If your seconds are measured from some other fixed point in time, I cannot guess which, and you have got a job to do to find out. Again decide which time zone you want to specify.

You could use SimpledateFormat.
new SimpleDateFormat("YYYY-MM-DD HH24:MI:SS").format(date)

Remove the day name from date and set it as only 'yyyy-MM-dd HH:mm:ss' [duplicate]

This question already has answers here:
Java Date changing format [duplicate]
(4 answers)
java.util.Date format conversion yyyy-mm-dd to mm-dd-yyyy
(8 answers)
Closed 5 years ago.
I'm trying to get the current day's date at 6 am in the format yyyy-MM-dd HH:mm:ss, but it shows as : Wed Dec 20 06:00:00 CST 2017
This is my code:
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd 06:00:00");
Date date0 = new Date();
String x = dateFormat.format(date0);
try{
DateFormat formatter ;
Date date ;
formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
date = formatter.parse(x);
}
catch (Exception e){}

java.util.Date is a container for the number of milliseconds since the Unix Epoch, it doesn't not maintain any kind of internal formatting concept, instead, when you print it, it use Date#toString which generally uses the current Locale to provide a human readable representation of the value.
While I'm sure you could continue to mess about with Date to make this work, a much simpler approach would be to take advantage of the newer Date/Time API, something like...
LocalDateTime now = LocalDateTime.now();
LocalDateTime then = now.withHour(6).withMinute(0).withSecond(0).withNano(0);
String formatted = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss").format(then);
System.out.println(formatted);
Which, for me, prints out 2017-12-21 06:00:00

TL;DR
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
LocalDate date0 = LocalDate.now(ZoneId.of("America/Winnipeg"));
String at6Am = date0.atTime(LocalTime.of(6, 0)).format(formatter);
System.out.println(at6Am);
Running just now this printed
2017-12-21 06:00:00
Details
The classes that you use, Date and SimpleDateFormat, have been around since Java 1.0, some 20 years. They have proved to be poorly designed and cumbersome to use. Maybe for that reason too, much has been written about them, and from searching the web you could easily get the impression that these are the classes you should use. On the contrary, they are the classes you should avoid. Their replacement came out with Java 8, it will soon be 4 years ago.
Formatters are for formatting and parsing. You shouldn’t use a formatter, even less two formatters, for changing the time-of-day to 6 AM.
It is never the same date everywhere on the globe. So getting today’s date is an operation that depends on a time zone. I have made the time zone explicit in my code so the reader will also be aware of this fact. Please substitute your desired time zone if it didn’t happen to be America/Winnipeg.
You are modifying existing software. If you got an old-fashioned Date object from it, first convert it to the modern Instant type, then use the modern API for further operations. For example:
Date date0 = getOldfashionedDateFromLegacyApi();
String at6Am = date0.toInstant()
.atZone(ZoneId.of("America/Winnipeg"))
.with(LocalTime.of(6, 0))
.format(formatter);
What went wrong in your code?
I don’t think there’s anything really wrong with the code in your question. You wanted your date-time formatted as 2017-12-20 06:00:00, and you got that in the string x in the third code line. Be happy with that and leave out the remainder of the code.
There is no such thing as imposing the format on the date-time objects, (no matter if we talk the outdated or the modern API). Formatting a date-time means converting it to a String in the desired format.

After parsing, you need to format it as follows: formatter.format(date). So modify your code as follows:
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd 06:00:00");
Date date0 = new Date();
String x = dateFormat.format(date0);
try{
DateFormat formatter ;
Date date ;
formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
date = formatter.format(formatter.parse(x));
}
catch (Exception e){}

Java - SimpleDateFormat formatter to return epoch time with milliseconds [duplicate]

This question already has answers here:
Convert a date format in epoch
(6 answers)
Closed 5 years ago.
I am very new to Java and coding in general - I have some code which returns a timestamp in the following format yyyy.MM.dd HH:mm:ss:ms which is shown below:
SimpleDateFormat formatter = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss:sss");
This returns:
2017.07.19 11:42:30:423
Is there a way to edit the "SimpleDateFormat formatter" code above to return the date/time as an epoch timestamp that includes milliseconds so that the value returned is formatted as per the below?
1500464550423
I'm hoping that I can amend the ("yyyy.MM.dd HH:mm:ss:sss") part of the SimpleDateFormat formatter code to do this.
Any help or advice is much appreciated.
Thanks

You have a simple error in the use of case in your format pattern string (these are case sensitive). And worse, you are using the old and troublesome SimpleDateFormat class. One of the many problems with it is it’s not telling you what the problem is.
So I recommend you use the modern Java date and time API instead (I am deliberately using your format pattern string verbatim):
String receivedTimetamp = "2017.07.19 11:42:30:423";
DateTimeFormatter parseFormatter
= DateTimeFormatter.ofPattern("yyyy.MM.dd HH:mm:ss:sss");
LocalDateTime dateTime = LocalDateTime.parse(receivedTimetamp, parseFormatter);
System.out.println(dateTime);
This code throws an IllegalArgumentException: Too many pattern letters: s. I hope this calls your awareness to the fact that you are using two s’s for seconds and three s’s for fraction of second. If it still isn’t clear, the documentation will tell you that lowercase s is correct for seconds, while you need uppercase S for the fraction. Let’s repair:
DateTimeFormatter parseFormatter
= DateTimeFormatter.ofPattern("yyyy.MM.dd HH:mm:ss:SSS");
Now the code prints 2017-07-19T11:42:30.423, so we have managed to parse the string correctly.
To convert to milliseconds we are still missing a crucial piece of information: in what time zone should the timestamp be interpreted? I think the two obvious guesses are UTC and your local time zone (which I don’t know). Try UTC:
System.out.println(dateTime.atOffset(ZoneOffset.UTC).toInstant().toEpochMilli());
This produces 1500464550423, which is the number you asked for. I suppose we’re done.
If you wanted your JVM’s time zone setting instead, use .atZone(ZoneId.systemDefault()) instead of .atOffset(ZoneOffset.UTC), but beware that the setting may be altered by other software running in the same JVM, so this is fragile.

First of all, check the documentation of SimpleDateFormat. The pattern that corresponds to milliseconds is an uppercase S, while the lowercase s corresponds to seconds. The problem is that SimpleDateFormat usually doesn't complain and try to parse 423 as seconds, adding this amount to your end date (giving an incorrect result).
Anyway, SimpleDateFormat just parses a String to a java.util.Date or formats the Date to a String. If you want the epoch millis value, you must get it from the Date object:
// input string
String s = "2017.07.19 11:42:30:423";
// use correct format ('S' for milliseconds)
SimpleDateFormat formatter = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss:SSS");
// parse to a date
Date date = formatter.parse(s);
// get epoch millis
long millis = date.getTime();
System.out.println(millis); // 1500475350423
The problem is that SimpleDateFormat uses the system's default timezone, so the final value above (1500475350423) will be equivalent to the specificed date and time in my system's timezone (which can be different from yours - just for the record, my system's default timezone is America/Sao_Paulo). If you want to specify in what timezone this date is, you need to set in the formatter (before calling parse):
// set a timezone to the formatter (using UTC as example)
formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
With this, the result for millis will be 1500464550423 (the equivalent to the specificed date and time in UTC).
To do the opposite (create a date from the millis value), you must create a Date object and then pass it to the formatter (also taking care of setting a timezone to the formatter):
// create date from millis
Date date = new Date(1500464550423L);
// use correct format ('S' for milliseconds)
SimpleDateFormat formatter = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss:SSS");
formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
// format date
String formatted = formatter.format(date);
Java new date/time API
The old classes (Date, Calendar and SimpleDateFormat) have lots of problems and design issues, and they're being replaced by the new APIs.
If you're using Java 8, consider using the new java.time API. It's easier, less bugged and less error-prone than the old APIs.
If you're using Java <= 7, you can use the ThreeTen Backport, a great backport for Java 8's new date/time classes. And for Android, there's the ThreeTenABP (more on how to use it here).
The code below works for both.
The only difference is the package names (in Java 8 is java.time and in ThreeTen Backport (or Android's ThreeTenABP) is org.threeten.bp), but the classes and methods names are the same.
As the input String has no timezone information (only date and time), first I parsed it to a LocalDateTime (a class that represents a date and time without timezone). Then I convert this date/time to a specific timezone and get the millis value from it:
// input string
String s = "2017.07.19 11:42:30:423";
// use correct format ('S' for milliseconds)
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy.MM.dd HH:mm:ss:SSS");
// as the input string has no timezone information, parse it to a LocalDateTime
LocalDateTime dt = LocalDateTime.parse(s, formatter);
// convert the LocalDateTime to a timezone
ZonedDateTime zdt = dt.atZone(ZoneId.of("Europe/London"));
// get the millis value
long millis = zdt.toInstant().toEpochMilli(); // 1500460950423
The value is now 1500460950423, equivalent to the specified date and time in London timezone.
Note that the API uses IANA timezones names (always in the format Region/City, like America/Sao_Paulo or Europe/Berlin).
Avoid using the 3-letter abbreviations (like CST or PST) because they are ambiguous and not standard.
You can get a list of available timezones (and choose the one that fits best your system) by calling ZoneId.getAvailableZoneIds().
You can also use ZoneOffset.UTC constant if you want to use UTC.
To do the opposite, you can get the millis value to create an Instant, convert it to a timezone and pass it to the formatter:
// create Instant from millis value
Instant instant = Instant.ofEpochMilli(1500460950423L);
// use correct format ('S' for milliseconds)
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy.MM.dd HH:mm:ss:SSS");
// convert to timezone
ZonedDateTime z = instant.atZone(ZoneId.of("Europe/London"));
// format
String formatted = z.format(formatter);

First advice is to move to java8 java.time API instead of learning the broken java.date API
then do:
Instant i = Instant.now();
System.out.println(i.toEpochMilli());
in your case you can do:
LocalDateTime myldt = LocalDateTime.parse("2017-06-14 14:29:04",
DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
System.out.println(myldt.toInstant(ZoneOffset.UTC).toEpochMilli());
note that as soon as you play more with the api you will find more ways to achieve the same thing, at the end you will end invoking toEpochMilli

String strDate = "Jun 13 2003 23:11:52.454 UTC";
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("MMM dd yyyy HH:mm:ss.SSS zzz");
ZonedDateTime zdt = ZonedDateTime.parse(strDate,dtf);
System.out.println(zdt.toInstant().toEpochMilli()); // 1055545912454

You can try
long time = System.currentTimeMillis();

If you have a java.util.Date then invoking getTime() will return the number of millis since the epoch. For example:
SimpleDateFormat formatter = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss:sss");
Date dateToBeFormatted = new Date();
// this will print a datetime literal on the above format
System.out.println(formatter.format(dateToBeFormatted));
// this will print the number of millis since the Java epoch
System.out.println(dateToBeFormatted.getTime());
The key point here is that in order to get the number of millis since the epoch you do not need a SimpleDateFormatter because the number of millis since the epoch is a property of the Date.

Convert Date to DateTime using Joda [duplicate]

This question already has answers here:
Converting a date string to a DateTime object using Joda Time library
(10 answers)
Closed 6 years ago.
Is there a way to convert a date in the format "YYYY-MM-dd" to "YYYY-MM-dd HH:mm:ss" using Joda?
Eg: "2016-01-21" to "2016-01-21 00:00:00"

Use DateTimeFormat class from Joda API. It helps you to format the date to the formatting of your choice. You can simply provide the format you want, like in this case you want "YYYY-MM-dd HH:mm:ss". The code below works with JodaTime 2.0 and above.
DateTime date = DateTime.parse("2016-01-21", DateTimeFormat.forPattern("YYYY-MM-dd HH:mm:ss"));
There are two things in play here, first we need to parse the existing string into a DateTime object, which is done via the parse method, it also allows an additional argument, to convert the output into a different format. The longer but easier to understand implementation is given below.
DateTime date = DateTime.parse("2016-01-21");
DateTimeFormatter formatter = DateTimeFormat.forPattern("YYYY-MM-dd HH:mm:ss");
date = formatter.parseDateTime(string);

Your question is not clear:
Do you want to just format "something representing a date" into a string with time of "00:00:00"?
Or are you trying to convert "something representing a date" into "something representing a date+time, with 00:00:00 as time"?
Or are you trying to convert a java.util.Date to a Joda org.joda.time.DateTime by ignoring the original time and set time to 00:00:00?
Or are you trying to convert a string of date with format of "YYYY-MM-dd" to another String with date+time, with 00:00:00 as time?
Or something else?
In Joda, the proper way to represent a date is by LocalDate, and the proper way to represent a "date + time" information (but not a instant of time) is by LocalDateTime. DateTime is representing a instant of time. With these basic understanding:
Answer for Q1:
String result = DateTimeFormat.forPattern("YYYY-MM-dd", myLocalDate);
Answer for Q2:
LocalDateTime result = myLocalDate.toLocalDateTime(LocalTime.MIDNIGHT);
Answer for Q3:
DateTime result = new DateTime(javaUtilDate).withTimeAtStartOfDay();
Answer for Q4:
String result = dateString + " 00:00:00";