Developing an Application where i have to parse the following date:
2015-02-02T11:21:51.895Z
using SimpleDateFormat class. But I am getting a Date Parsing Exception.
Here is my code snippet:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd'T'hh:mm:ss'Z'");`
Date qdate = new GregorianCalendar(0,0,0).getTime();
try {
qdate = sdf.parse(dt);
} catch (ParseException e) {
}
Regarding your input "2015-02-02T11:21:51.895Z" you should see that your assumed pattern does not match the input because the pattern does not expect the millisecond part but the literal "Z".
Beyond this, the pattern you used is wrong because of following reasons:
m = minute
M = month
h = hour of half day (1-12)
H = hour of full day (0-23)
X = timezone designator (because Z is not a literal but stands for UTC+00:00)
So you need (please also refer to javadoc):
yyyy-MM-dd'T'HH:mm:ss.SSSX
There is an error in your format (add .SSS for the miliseconds):
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd'T'hh:mm:ss.SSS'Z'");
Date date = sdf.parse("2015-02-02T11:21:51.895Z");
Related
Im just wondering. is it ok to combine years,month, and day of two date and make a comparison based on the combination.
eg:
Date A: 12th-January-2019
Date B: 24th-December-2018
Based on the above date, i could combine the year,month, and day as follow:
Date A: 20190112
Date B: 20181224
So based on the numbers, i could do logic like below to compare which date comes first:
if(Date A > Date B) {
output("Date A is the latest")
}
i would like to implement this method just to compare which is the latest date.
are there any problem of doing so.
java.time
Since you are using Java, I suggest that you take advantage of java.time, the modern Java date and time API.
String[] dateStringsFromDatabase = {
"2018/12/19",
"2017-02-01",
"2018.03.04",
"25-12-2016", // reversed
"2019\\09\\12",
"2014:03:01"
};
List<LocalDate> parsedDates = new ArrayList<>(dateStringsFromDatabase.length);
for (String dateString : dateStringsFromDatabase) {
// No matter which delimiter is used, replace it with a hyphen
String text = dateString.replaceAll("\\W", "-");
try {
parsedDates.add(LocalDate.parse(text));
} catch (DateTimeParseException dtpe) {
System.out.println(dateString + " not parsed: " + dtpe.getMessage());
}
}
Output:
25-12-2016 not parsed: Text '25-12-2016' could not be parsed at index 0
What this approach buys you is validation of the dates even though they come with all different delimiters. Especially in this situation I believe that you should want to validate that your strings are within the expected variations. Otherwise you risk that a date with the numbers reversed ends up as a date in year 2512, for example. You want to catch that before it happens.
Example of comparing which comes first:
for (int i = 1; i < parsedDates.size(); i++) {
LocalDate dateA = parsedDates.get(i - 1);
LocalDate dateB = parsedDates.get(i);
if (dateA.isAfter(dateB)) {
System.out.format("%s is later than %s%n", dateA, dateB);
}
}
Output:
2018-12-19 is later than 2017-02-01
2019-09-12 is later than 2014-03-01
Link: Oracle tutorial: Date Time explaining how to use java.time.
Im trying to convert the first two columns of a cell into a Matlab time. First column {1,1} is the date in YYYY-MM-DD format and the second is the time in HH:MM format.
Any ideas where I'm going wrong? My code:
file = 'D:\Beach Erosion and Recovery\Bournemouth\Bournemouth Tidal
Data\tidal_data_jtide.txt'
fileID = fopen(file);
LT_celldata = textscan(fileID,'%D%D%D%D%d%[^\n\r]','delimiter',',');
formattime = 'yyyy-mm-dd HH:MM'
date = LT_celldata{1,1};
time = LT_celldata{1,2};
date_time = datenum('date','time'); code
Screenshot below is LT_celldata{1,1} :
You can combine variables date and time with the following code:
date = datetime(LT_celldata{1,1},'InputFormat','yyyy-MM-dd');
time = datetime(LT_celldata{1,2},'InputFormat','HH:mm:ss','Format','HH:mm:ss');
myDatetime = datetime(date + timeofday(time),'Format','yyyy-MM-dd HH:mm:ss');
The code uses timeofday function to combine date and time information from the two different variables. You may find more information and examples at this documentation page.
What I am encountering is quite peculiar.
My Code:
val aa = "2017-01-17 01:33:00"
val bb = "04:33"
val hour = bb.substring(0, bb.indexOf(":"))
val mins = bb.substring(bb.indexOf(":") + 1, bb.length())
val negatedmins = "-" + mins
val ecoffsethour = hour.toLong
val ecoffsetmins = negatedmins.toLong
println(aa)
val datetimeformatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")
val txn_post_date_hkt_date_parsed = LocalDateTime.parse(aa, datetimeformatter)
println(txn_post_date_hkt_date_parsed)
val minushours = txn_post_date_hkt_date_parsed.minusHours(ecoffsethour)
println(minushours)
val minusmins = minushours.minusMinutes(ecoffsetmins)
println(minusmins)
val offsetPostdateDiff = minusmins.toString().replace("T", " ")
println(offsetPostdateDiff)
Output:
2017-01-17 01:33:00
2017-01-17T01:33
2017-01-16T21:33
2017-01-16T22:06
2017-01-16 22:06
In the same code I am changing only the "aa" value to ==> 2017-01-17 01:33:44
Now the output is :
2017-01-17 01:33:44
2017-01-17T01:33:44
2017-01-16T21:33:44
2017-01-16T22:06:44
2017-01-16 22:06:44
Why is the first method not taking seconds field into consideration?
My Requirement is : However the output should come in "yyyy-MM-dd
HH:mm:ss" format.
I'm quite new to Scala. Please enlighten me.
Default format is ISO 8601
The java.time classes use the standard ISO 8601 formats by default when parsing/generating strings to represent date-time value.
The standard format for a local date-time is what you are seeing with the T in the middle: YYYY-MM-DDTHH:MM:SS.SSSSSSSSS.
LocalDateTime ldt = LocalDateTime.now( ZoneId.of( "America/Montreal" ) ) ;
String output = ldt.toString() ;
2017-01-23T12:34:56.789
Your call println( txn_post_date_hkt_date_parsed ) is implicitly calling the built-in toString method on the LocalDateTime object, and thereby asking for the standard ISO 8601 format with the T.
println( txn_post_date_hkt_date_parsed.toString() )
Offsets
On an unrelated note, you are working too hard. The java.time classes handle offsets. I do not understand why you want an offset of such an odd number (four hours and thirty-three minutes), but so be it.
Here is your code revised, but in Java syntax.
String input = "2017-01-17 01:33:00" ;
DateTimeFormatter f = DateTimeFormatter.ofPattern( "yyyy-MM-dd HH:mm:ss" ) ;
LocalDateTime ldt = LocalDateTime.parse( input , f ) ;
OffsetDateTime utc = ldt.atOffset( ZoneOffset.UTC ) ;
ZoneOffset offset = ZoneOffset.of( "-04:33" ) ; // Behind UTC by four hours and thirty-three minutes.
OffsetDateTime odt = utc.withOffsetSameInstant( offset ) ;
You can see this code run live at IdeOne.com. Notice how the wall-clock time of your offset-from-UTC is on the previous date. Same moment in history, same point on the timeline, but viewed through two different wall-clock times (UTC, and four hours and thirty three minutes behind).
The Z on the end is standard ISO 8601 notation, short for Zulu and meaning UTC.
input: 2017-01-17 01:33:00
ldt.toString(): 2017-01-17T01:33
utc.toString(): 2017-01-17T01:33Z
odt.toString(): 2017-01-16T21:00-04:33
It's usually better to explicitly the format in which you want the output.
So, instead of
println datetime
You can do something like this:
println datetimeformat.print(datetime)
Good luck!
Edit: Change made to make the 2 expressions exactly equivalent
I'm having trouble finding a good way of formatting a UTC-time stamp with this format: yyyyMMdd-HH:mm:ss.<three additional digits>
I wasn't able to find any character that represents milliseconds/hundredths, I'm not even sure this is possible, to parse that format that is.
Ideally I'd like to use the parseToStringDate that's part of the Date library.
My plan b is to convert yyyyMMdd-HH:mm:ss to milliseconds and then add the three last digits to that number.
Use yyyyMMdd-HH:mm:ss.SSS
This will get you milliseconds as well.
Test Code:
def now = new Date()
println now.format("yyyyMMdd-HH:mm:ss.SSS", TimeZone.getTimeZone('UTC'))
I would convert it like that:
def now = new Date()
println now.format("YYYYMMdd-HH:mm:ss")
You can try this:
TimeZone.getTimeZone('UTC')
Date date = new Date()
String newdate = date.format("YYYY-MM-dd HH:mm:ss.Ms")
log.info newdate
I am using ColdFusion 9.0.1 and some database that I cannot change.
I am accessing a database that stores a date as an eight digit numeric with zero decimal places like this:
YYYYMMDD
I need to be able to read the date, add and subtract days from a date, and create new dates. I am looking for a ColdFusion solution to efficiently (not much code) to convert the date to our standard format, which is
MM/DD/YYYY
And then convert it back into the database's format for saving.
I need to code this in such a way that non-ColdFusion programmers can easily read this and use it, copy and modify it for other functions (such as adding a day to a date). So, I am not looking for the most least amount of code, but efficient and readable code.
Can you suggest anything that would make this code block more flexible, readable, or more efficient (less code)?
<cfscript>
// FORMAT DB DATE FOR BROWSER
DateFromDB = "20111116";
DatedToBrowser = createBrowserDate(DateFromDB);
writeOutput(DatedToBrowser);
function createBrowserDate(ThisDate) {
ThisYear = left(ThisDate, 4);
ThisMonth = mid(ThisDate, 4, 2);
ThisDay = right(ThisDate, 2);
NewDate = createDate(ThisYear, ThisMonth, ThisDay);
NewDate = dateFormat(NewDate, "MM/DD/YYYY");
return NewDate;
}
// FORMAT BROWSER DATE FOR DB
DateFromBrowser = "11/16/2011";
DateToDB = createDBDate(DateFromBrowser);
writeDump(DateToDB);
function createDBDate(ThisDate) {
ThisYear = year(ThisDate);
ThisMonth = month(ThisDate);
ThisDay = day(ThisDate);
NewDate = "#ThisYear##ThisMonth##ThisDay#";
return NewDate;
}
</cfscript>
First find who ever did the database and kick them in the nads...
Personally I'd Convert with sql so my code only dealt with date objects.
Select Convert(DateTime, Convert(VarChar(8),DateTimeInventedByIdjitColumn))
From SomeTable
As stated by our peers, store dates as dates.
'08/06/2011' could be 8th of june of the 6th of August depending on locale.
20111643 is a valid integer..
Not using a proper date type is just a massive collection of features and bugs that at best are waiting to happen.
You can actually rewrite each function into 1 line of code.
function createBrowserDate(ThisDate) {
return mid(ThisDate,4,2) & "/" & right(ThisDate,2) & "/" & left(ThisDate,4);
}
and
function createDBDate(ThisDate) {
return dateFormat( ThisDate, "YYYYMMDD" );
}
Don't keep dates as strings - keep dates as dates and format them when you need to.
If you can't correct the database to use actual date columns (which you should if you can), then you can use these two functions to convert to/from YYYYMMDD and a date object:
function parseYMD( YYYYMMDD )
{
if ( ! refind('^\d{8}$' , Arguments.YYYYMMDD ) )
throw "Invalid Format. Expected YYYYMMDD";
return parseDateTime
( Arguments.YYYYMMDD.replaceAll('(?<=^\d{4})|(?=\d{2}$)','-') );
}
function formatYMD( DateObj )
{
return DateFormat( DateObj , 'yyyymmdd' );
}
By using date objects it means that any level of developer can work with them, without needing to care about formatting, via built-in functions like DateAdd, DateCompare, and so on.
I'm not a regular expression fan since it's not that readable to me.
Since you're using CF9, I'd typed the argument and specify the returntype of the functions to be even more readable for the next person picking up your code.
First, right after I read the date from DB, I'd parse it to a Date object using parseDBDate()
Date function parseDBDate(required String dbDate)
{
var yyyy = left(dbDate, 4);
var mm = mid(dbDate, 4, 2);
var dd = right(dbDate, 2);
return createDate(yyyy , mm, dd);
}
Once you have the date object, you can use all those built-in Date functoin like DateAdd() or DateDiff().
Call browserDateFormat() right before you need to display it.
String function browserDateFormat(required Date date)
{
return dateFormat(date, "MM/DD/YYYY");
}
Call dBDateFormat() inside <cfqueryparam value=""> when it's time to persist to DB
String function dBDateFormat(required Date date)
{
return dateFormat(date, "YYYYMMDD");
}
One liner :)
myDateString = "20110203";
myCfDate = createObject("java","java.text.SimpleDateFormat").init("yyyyMMdd").parse(myDateString,createObject("java","java.text.ParsePosition").init(0*0));
If you want to parse different patterns, change "yyyyMMdd" to any other supported pattern.
http://download.oracle.com/javase/1.5.0/docs/api/java/text/SimpleDateFormat.html
The ParsePosition is used to say where to start parsing the string.
0*0 is shorthand for JavaCast("int",0) - in the Adobe cf engine, 0 is a string, until you apply math to it, then it becomes a Double, which the ParsePosition constructor supports. Technically, it constructs with an int, but cf is smart enough to downgrade a Double to an int.
http://download.oracle.com/javase/1.5.0/docs/api/java/text/ParsePosition.html