So I am trying to convert a string into an iso format for the date.
This is the string that I am trying to convert "2016-07-05 02:14:35.0"
I would like to have it in this format the iso 8601
"2016-07-05T02:14:35.0"
I have this so far
DateTimeFormatter format = DateTimeFormat.forPattern("YYYY-MM-DDTHH:mm:sszzz");
new LocalDate();
LocalDate newDate = LocalDate.parse(created,format);
created = newDate.toString();
But it is giving me this exception
ERROR: Illegal pattern component: T; nested exception is java.lang.IllegalArgumentException: Illegal pattern component: T
I followed the examples and I don't know what I am doing wrong here.
Any help would be appreciated.
Firstly, that value is a LocalDateTime, not a LocalDate. If you want to get a date out in the end, I'd convert it to a LocalDateTime first, then take the date part of that.
When performing date formatting and parsing, always read the documentation really carefully. It looks like you're using Joda Time (due to using forPattern; if you can move to Java 8 that would be beneficial). That means you should be reading the DateTimeFormat docs.
Current problems with your pattern:
You're using 'D' instead of 'd'; that means day-of-year
You've specified 'T' without quoting it, and it isn't in the pattern anyway
You've ignored the fraction-of-second part of your value
You've specified 'zz' when there's no time zone indicator in the value.
Here's a working example:
import org.joda.time.*;
import org.joda.time.format.*;
public class Test {
public static void main(String[] args) {
String text = "2016-07-05 02:14:35.0";
DateTimeFormatter format = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss.S");
LocalDateTime localDateTime = LocalDateTime.parse(text, format);
System.out.println(localDateTime);
}
}
If you actually want to parse values with T in the middle, you'd use a pattern of "yyyy-MM-dd'T'HH:mm:ss.S" - note how then the T is quoted so it's treated literally instead of as a format specifier.
Note that this is just parsing. It's not "converting a string into ISO date format" - it's converting a string into a LocalDateTime. If you then want to format that value in an ISO format, you need to be using DateTimeFormatter.print, with an appropriate format. For example, you might want to convert to a format of yyyy-MM-dd'T'HH:mm:ss.S':
import org.joda.time.*;
import org.joda.time.format.*;
public class Test {
public static void main(String[] args) {
String text = "2016-07-05 02:14:35.0";
DateTimeFormatter parser = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss.S");
LocalDateTime localDateTime = LocalDateTime.parse(text, parser);
DateTimeFormatter printer = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.S");
String formatted = printer.print(localDateTime);
System.out.println(formatted); // Output 2016-07-05T02:14:35.0
}
}
The code above will only handle a single digit fraction-of-second. You could parse using .SSS instead of .S, but you really need to work out what you want the output to be in different cases (e.g. for 100 milliseconds, do you want .1 or .100?).
You have some errors in your code:
The pattern should be 'yyyy-MM-dd HH:mm:ss.SSS'. Be aware of upper-
and lowercase.
Use LocalDateTime to get date and time. LocalDate only holds the date.
The corrected code:
String created = "2016-07-05 02:14:35.000";
DateTimeFormatter format = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS");
LocalDateTime newDate = LocalDateTime.parse(created,format);
created = newDate.toString();
System.out.println(created);
Use the following format to convert
String format = "yyyy-mm-dd hh:mm:ss"
You are using the wrong format to convert. Using T is only to separate the date from time.
Use the format like this
String = "yyyy-MM-dd'T'HH:mm:ss"
Related
I have a situation where I need to convert one Java date time format into another but have been having just a bear of a time doing so. Been searching for solutions a long time and have tried many things that have just not worked but I'm at my wits end :(.
I have to convert from
yyyy-MM-dd'T'HH:mm:ss
to
MM/dd/yyyy HH:mm:ss
This is the last thing I've tried, but alas it has no effect at all at transforming the pattern:
private Instant convertInstantFormat(Instant incomingDate) {
DateTimeFormatter formatter = DateTimeFormatter.ofPattern(AUTH_DATE_PATTERN)
.withZone(ZoneId.systemDefault());
return Instant.parse(formatter.format(incomingDate));
}
Where
AUTH_DATE_PATTERN = "MM/dd/yyyy HH:mm:ss";
incomingDate = 2021-10-22T06:39:13Z
and outgoing date = 2021-10-22T06:39:13Z
I'm sure this is probably just the most naive attempt.
I've tried standardizing the date format and then reformatting, but no go.
I'm just sort of out of steam.
As always, any and all help from this incredible community is tremendously appreciated!
UPDATE
I just wanted to point out that the input and output to this method are of type "Instant."
Apologies for not making this clear initially.
I have to convert from yyyy-MM-dd'T'HH:mm:ss to MM/dd/yyyy HH:mm:ss
Your incoming date time format is ISO_LOCAL_DATE_TIME.
String datetime = "2021-12-16T16:22:34";
LocalDateTime source = LocalDateTime.parse(datetime,DateTimeFormatter.ISO_LOCAL_DATE_TIME);
// desired output format
String AUTH_DATE_PATTERN = "MM/dd/yyyy HH:mm:ss";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern(AUTH_DATE_PATTERN);
String output = source.format(formatter);
System.out.println(output);
prints
12/16/2021 16:22:34
If your incoming date is 2021-10-22T06:39:13Z that is a zoned date time and can be parsed-from/formatted-to using
DateTimeFormatter.ISO_ZONED_DATE_TIME.
tl;dr
Instant // Represents a point on the time line.
.parse( "2021-10-22T06:39:13Z" ) // Returns an `Instant` object. By default, parses text in standard ISO 8601 for at where `Z` means offset of zero.
.atOffset( ZoneOffset.UTC ) // Returns an `OffsetDateTime` object.
.format(
DateTimeFormatter.ofPattern( "MM/dd/uuuu HH:mm:ss" )
) // Returns a `String` object.
See this code run live at IdeOne.com.
10/22/2021 06:39:13
Details
You said:
incomingDate = 2021-10-22T06:39:13Z
Your formatting pattern fails to match your input string.
Your input string happens to comply with the ISO 8691 format used by default in Instant.parse. So no need to specify a formatting pattern.
Instant instant = Instant.parse( "2021-10-22T06:39:13Z" ) ;
The Z on the end means an offset of zero hours-minutes-seconds from the prime meridian of UTC.
You asked to generate text representing that moment in the format of MM/dd/yyyy HH:mm:ss. I recommend including an indicator of the offset or time zone. But it you insist on omitting that, read on.
Convert from the basic class Instant to the more flexible OffsetDateTime class.
OffsetDateTime odt = instant.atOffset( ZoneOffset.UTC ) ;
Specify your formatting pattern.
DateTimeFormatter f = DateTimeFormatter.ofPattern( "MM/dd/uuuu HH:mm:ss" ) ;
Generate your desired text.
String output = odt.format( f ) ;
To learn more, search Stack Overflow. These topics have already been addressed many times.
Append timezone 'z' info at the end of the format pattern otherwise parsing throws an exception.
Here's a working example.
Unit Test (Passing)
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThat;
class DateFormatConverterTest {
#Test
void convertDate() {
final String incomingDate = "2021-10-22T06:39:13Z";
final String expectedOutgoingDate = "2021/10/22T06:39:13Z";
String actualOutgoingDate = new DateFormatConverter().convertDate(incomingDate);
assertThat(actualOutgoingDate).isEqualTo(expectedOutgoingDate);
}
}
Implementation
import java.time.format.DateTimeFormatter;
public class DateFormatConverter {
private static final DateTimeFormatter INCOMING_DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ssz");
private static final DateTimeFormatter OUTGOING_DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy/MM/dd'T'HH:mm:ssz");
String convertDate(String incoming) {
return OUTGOING_DATE_TIME_FORMAT.format(INCOMING_DATE_TIME_FORMAT.parse(incoming));
}
}
I am trying to convert java String date into java.sql.Timestamp. I am able to convert this by using SimpleDateFormat with String date value as "2021-01-07 02:02:16.172", but when trying with the value as "2021-08-04T00:00:00.000" with seperator 'T', it gives me error. Below is the java code:
import java.sql.Timestamp;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class DateTest {
public static void main(String[] args) throws ParseException {
//String date = "2021-08-04T00:00:00.000Z";// How to convert this?
String date = "2021-01-07 02:02:16.172";// conversion successful
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss.SSS");
Date parsedDate = dateFormat.parse(date);
Timestamp timestamp = new java.sql.Timestamp(parsedDate.getTime());
System.out.println(timestamp);
}
}
You could use the modern API for dates, times and related information (like offsets from UTC): java.time
Strings in different formats need to be handled differently:
your first example String is formatted in ISO standard, so it can be parsed without defining a custom format. The parsing implicitly uses a DateTimeFormatter.ISO_OFFSET_DATE_TIME, which will result in an OffsetDateTime
your seconds String lacks the 'T' between date and time as well as an offset, that means you can just directly parse it to a LocalDateTime
java.sql.Timestamp got methods for conversion to java.time classes, at least to/from an Instant and a LocalDateTime. Since an Instant is a well defined moment in time, you can derive it from an OffsetDateTime:
public static void main(String[] args) throws Exception {
// your two example datetimes
String isoDateTime = "2021-08-04T00:00:00.000Z";
String customDateTime = "2021-01-07 02:02:16.172";
// you will need a custom formatter for the second one
DateTimeFormatter customDtf = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss.SSS");
// parse the Strings to java.time objects
// ISO standard, no extra formatter needed for the first one
OffsetDateTime odt = OffsetDateTime.parse(isoDateTime);
// the second one requires the formatter defined above
LocalDateTime ldt = LocalDateTime.parse(customDateTime, customDtf);
// convert them into Timestamps
Timestamp tsOne = Timestamp.from(odt.toInstant());
Timestamp tsTwo = Timestamp.valueOf(ldt);
// and print them
System.out.println("First Timestamp: " + tsOne);
System.out.println("Second Timestamp: " + tsTwo);
}
The output of this is
First Timestamp: 2021-08-04 02:00:00.0
Second Timestamp: 2021-01-07 02:02:16.172
This would be the new style...
new SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ss.SSS");
would be the old style
I'm querying database and getting date in this format "01-SEP-22"
I want to convert this date into this format "yyyy-MM-dd" in Java. Is there any way I can do this.
java.time
I recommend that you use java.time, the modern Java date and time API, for your date work.
In order to parse the month abbreviation in all upper case (like SEP) we need to instruct it to apply case insensitive parsing.
We can use DateTimeFormatterBuilder to build a DateTimeFormatter with such an instruction.
private static final DateTimeFormatter oracleFormatter
= new DateTimeFormatterBuilder()
.parseCaseInsensitive()
.appendPattern("dd-MMM-uu")
.toFormatter(Locale.ROOT);
The rest goes smoothly:
String stringFromOracle = "01-SEP-22";
LocalDate date = LocalDate.parse(stringFromOracle, oracleFormatter);
String formattedString = date.toString();
System.out.println(formattedString);
Output is:
2022-09-01
For generating the string I am exploiting the fact that LocalDate.toString() gives the format that you asked for, so I am not using any formatter explicitly. The format is known as ISO 8601 and as this name says, is an international standard.
Suggestions for improvement
Don’t retrieve your date as a String from Oracle. Retrieve a LocalDate directly and save the parsing.
Don’t convert a date from one string format to another. In your program keep the date as a LocalDate. If you need to take string input (which is not the case here), parse the string into a LocalDate immediately. Only when you need to give string output (to the user or in data exchange with another system, for example), format the LocalDate into a string in the required format.
Links
Oracle tutorial: Date Time explaining how to use java.time.
Wikipedia article: ISO 8601
Question: Insert & fetch java.time.LocalDate objects to/from an SQL database such as H2
You can simply use DateTimeFormatter:
public String convertDate(String dateStr) throws ParseException {
String[] split = dateStr.split("-");
split[1] = split[1].substring(0, 1).toUpperCase() + split[1].substring(1).toLowerCase();
dateStr = String.join("-", split);
DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("dd-MMM-yy", Locale.ENGLISH);
LocalDate date = LocalDate.parse(dateStr, dateFormatter);
return date.toString();
}
#Test
public void test_convertDate() throws ParseException {
assertEquals("2022-09-01", convertDate("01-SEP-22"));
}
This question already has answers here:
Can’t rid of 'T' in LocalDateTime
(3 answers)
How to prevent auto-generated 'T' letter when parsing String to LocalDateTime using DateTimeFormatterBuilder [duplicate]
(1 answer)
Closed 2 years ago.
I'm trying to format Threeten datetime, from yyyy-MM-dd'T'HH:mm:ss to yyyy-MM-dd HH:mm:ss. Below is the code, I'm using to achieve the task.
public void testChangeFormat() {
DateTimeFormatter inputFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss");
DateTimeFormatter outputFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
LocalDateTime date1 = LocalDateTime.parse("2020-03-10T15:14:05", inputFormatter);
System.out.println(date1); // prints 2020-03-10T15:14:05
String formattedDate = outputFormatter.format(date1);
System.out.println(formattedDate); // prints 2020-03-10 15:14:05
LocalDateTime newFormattedDateTime = LocalDateTime.parse(formattedDate);
System.out.println(newFormattedDateTime);
}
Everything seems to work as expected until I try to parse the formattedDate to LocalDateTime, at LocalDateTime newFormattedDateTime = LocalDateTime.parse(formattedDate);
I even get the datetime formatted as 2020-03-10 15:14:05 using outputFormatter, but when I try to parse that to LocalDateTime, it gives me the following exception:
org.threeten.bp.format.DateTimeParseException: Text '2020-03-10 15:14:05' could not be parsed at index 10
Can somebody help me with this?
LocalDateTime.parse(formattedDate) are using DateTimeFormatter.ISO_LOCAL_DATE_TIME (that is format yyyy-MM-dd'T'HH:mm:ss). That's why you get the exception when trying to parse string that has format yyyy-MM-dd HH:mm:ss. You should use:
LocalDateTime.parse(formattedDate, outputFormatter) if you wnat to do the parse to LocalDateTime again for some reason.
Note:
You have the printed format you at line: outputFormatter.format(date1) right?
You seem to be confused between LocalDateTime and format (which is a string representation).
A LocalDateTime always has T in it when you print its object using System.out.println (which implicitly calls toString as you most likely already know) e.g.
System.out.println(LocalDateTime.now());
will output 2020-04-14T09:36:04.723994.
See below how the toString of LocalDateTime has been implemented:
#Override
public String toString() {
return date.toString() + 'T' + time.toString();
}
and therefore your following statement will always show 'T' in it:
System.out.println(newFormattedDateTime);
It's up to you to format a LocalDateTime into the String representation of your choice. As I have mentioned in the first line, formats are strings i.e. you format a LocalDateTime into a String representation where you can apply all the options provided by DateTimeFormatter.
The correct way of converting the formattedDate to LocalDateTime is by applying the corresponding format which is specified in outputFormatter.
LocalDateTime newFormattedDateTime = LocalDateTime.parse(formattedDate,outputFormatter);
How date and time are stored in a LocalDateTime object shouldn't be a concern. We can always create the string in the required format from it.
I want to convert the timestamp 2011-03-10T11:54:30.207Z to 10/03/2011 11:54:30.207. How can I do this? I want to convert ISO8601 format to UTC and then that UTC should be location aware. Please help
String str_date="2011-03-10T11:54:30.207Z";
DateFormat formatter ;
Date date ;
formatter = new SimpleDateFormat("dd/MM/yyyy hh:mm:ss.SSS");
date = (Date)formatter.parse(str_date);
System.out.println("output: " +date );
Exception :java.text.ParseException: Unparseable date: "2011-03-10T11:54:30.207Z"
Firstly, you need to be aware that UTC isn't a format, it's a time zone, effectively. So "converting from ISO8601 to UTC" doesn't really make sense as a concept.
However, here's a sample program using Joda Time which parses the text into a DateTime and then formats it. I've guessed at a format you may want to use - you haven't really provided enough information about what you're trying to do to say more than that. You may also want to consider time zones... do you want to display the local time at the specified instant? If so, you'll need to work out the user's time zone and convert appropriately.
import org.joda.time.*;
import org.joda.time.format.*;
public class Test {
public static void main(String[] args) {
String text = "2011-03-10T11:54:30.207Z";
DateTimeFormatter parser = ISODateTimeFormat.dateTime();
DateTime dt = parser.parseDateTime(text);
DateTimeFormatter formatter = DateTimeFormat.mediumDateTime();
System.out.println(formatter.print(dt));
}
}
Yes. you can use SimpleDateFormat like this.
SimpleDateFormat formatter, FORMATTER;
formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
String oldDate = "2011-03-10T11:54:30.207Z";
Date date = formatter.parse(oldDate.substring(0, 24));
FORMATTER = new SimpleDateFormat("dd-MMM-yyyy HH:mm:ss.SSS");
System.out.println("OldDate-->"+oldDate);
System.out.println("NewDate-->"+FORMATTER.format(date));
Output
OldDate-->2011-03-10T11:54:30.207Z
NewDate-->10-Mar-2011 11:54:30.207
Enter the original date into a Date object and then print out the result with a DateFormat. You may have to split up the string into smaller pieces to create the initial Date object, if the automatic parse method does not accept your format.
Pseudocode:
Date inputDate = convertYourInputIntoADateInWhateverWayYouPrefer(inputString);
DateFormat outputFormat = new SimpleDateFormat("MM/dd/yyyy hh:mm:ss.SSS");
String outputString = outputFormat.format(inputDate);
You might want to have a look at joda time, which is a little easier to use than the java native date tools, and provides many common date patterns pre-built.
In response to comments, more detail:
To do this using Joda time, you need two DateTimeFormatters - one for your input format to parse your input and one for your output format to print your output. Your input format is an ISO standard format, so Joda time's ISODateTimeFormat class has a static method with a parser for it already: dateHourMinuteSecondMillis. Your output format isn't one they have a pre-built formatter for, so you'll have to make one yourself using DateTimeFormat. I think DateTimeFormat.forPattern("mm/dd/yyyy kk:mm:ss.SSS"); should do the trick. Once you have your two formatters, call the parseDateTime() method on the input format and the print method on the output format to get your result, as a string.
Putting it together should look something like this (warning, untested):
DateTimeFormatter input = ISODateTimeFormat.dateHourMinuteSecondMillis();
DateTimeFormatter output = DateTimeFormat.forPattern("mm/dd/yyyy kk:mm:ss.SSS");
String outputFormat = output.print( input.parseDate(inputFormat) );
Hope this Helps:
public String getSystemTimeInBelowFormat() {
String timestamp = new SimpleDateFormat("yyyy-mm-dd 'T' HH:MM:SS.mmm-HH:SS").format(new Date());
return timestamp;
}
Use DateFormat. (Sorry, but the brevity of the question does not warrant a longer or more detailed answer.)