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Simple Date Parsing

I've been struggling a strange question.
I'm trying to parse a date format looks like this
"Thu, 18 Aug 2016 16:25:25 GMT"
to only Month and date like this
"08/18"
well I use two SimpleDateFormat, to parse and format the input and output
DateFormat inputFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z");
DateFormat outputFormat = new SimpleDateFormat("MM/dd");
however, everything seems to be correct when using genymotion emulator
but when it comes to the real phone, say sony Xperia Care
the following questions kept on comming
java.text.ParseException: Unparseable date: "Wed, 10 Aug 2016 15:40:57 GMT" (at offset 0)
so whats the reason that this happens?

Try to use
new SimpleDateFormat("EE MMM dd HH:mm:ss z yyyy",Locale.ENGLISH);

Your String-DAte has information that is related to an specific language, therefor you need to prepare the SimpleDAteFormat for such an information.
ERGO: you need to give a Locale
Example:
public static void main(String[] args) throws ParseException {
String dateStr = "Thu, 18 Aug 2016 16:25:25 GMT";
DateFormat inputFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z", Locale.ENGLISH);
Date d = null;
d = inputFormat.parse(dateStr);
DateFormat outputFormat = new SimpleDateFormat("MM/dd");
System.out.println("After format: " + outputFormat.format(d));
}

Trouble parsing Java Date Object?

I am receiving a Java Date formatted like so: "Sun Sep 14 02:00:00 PDT 2014" into a yyyy-MM-dd format but I can't seem to parse it. What I tried is the following:
String time = "Sun Sep 14 02:00:00 PDT 2014";
SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd");
Date contractEffectiveDateFormat = f.parse(time);
System.out.println("Date: " + contractEffectiveDateFormat);
However, I get an error saying that this date is unparsable. I'm not sure how to go about parsing this date because if I try to parse the date using the following:
DateFormat df = new SimpleDateFormat("EEE MMM dd kk:mm:ss z yyyy");
which is how to actually parse the date correctly into a Date object,
the string would turn into a Date object, but I can't seem to do anything with it from there. I want to turn it in so that it looks like 2014-09-14. Any ideas on how to do so? Thanks!

Use two DateFormat(s) one for input and for output,
String time = "Sun Sep 14 02:00:00 PDT 2014";
DateFormat out = new SimpleDateFormat("yyyy-MM-dd");
DateFormat in = new SimpleDateFormat("EEE MMM dd kk:mm:ss z yyyy");
try {
Date effectiveDate = in.parse(time);
System.out.println("Date: " + out.format(effectiveDate));
} catch (ParseException e) {
e.printStackTrace();
}
Output is the requested
Date: 2014-09-14

Your incoming string is this String time = "Sun Sep 14 02:00:00 PDT 2014";
which means the SimpleDateFormat pattern should match the incoming String pattern so you need to use SimpleDateFormat like this
DateFormat inFormat=new SimpleDateFormat("EEE MMM dd kk:mm:ss z yyyy",Locale.ENGLISH);
Then when you called parse() on inFormat it will give you Date Object which doesnot have particular format associated with it. So in order to format the Date again you need to create SimpleDateFormat object specifying the format you want which is this
DateFormat outFormat = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH);
Ultimately bind all together
One more thing always specify the Locale
String time = "Sun Sep 14 02:00:00 PDT 2014";
DateFormat outFormat = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH);
// good practice to specify the locale
DateFormat inFormat=new SimpleDateFormat("EEE MMM dd kk:mm:ss z yyyy",Locale.ENGLISH);
try {
Date parsedDate = inFormat.parse(time);
System.out.println("Required Formatted Date: " + outFormat.format(effectiveDate));
} catch (ParseException e) {
e.printStackTrace();
}

Simply add another SimpleDateFormat that'll allow you to present the Date object the way you want:
public static void main(String[] args) throws ParseException {
String time = "Sun Sep 14 02:00:00 PDT 2014";
DateFormat df = new SimpleDateFormat("EEE MMM dd kk:mm:ss z yyyy");
Date contractEffectiveDateFormat = df.parse(time);
System.out.println("Date: " + contractEffectiveDateFormat);
SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd");
System.out.println(f.format(contractEffectiveDateFormat)); // prints 2014-09-14
}

Getting the month and day from a TimeStamp

I have a String timeStamp in this format "Wed, 29 Jan 2014 20:14:15 GMT". I want to be able to compare this date with another date that is in this format 01/25/1999. I have tried simpledateformatter but with no success.
String a = connection.getHeaderField("Last-Modified"); //Returns Wed, 29 Jan 2014 20:14:15 GMT
Date lastModDate = new Date(file.lastModified()); //returns 01/25/1999
This is the simpleDateFormatter I tried implementing
SimpleDateFormat formatter;
Date dateIn = null;
formatter = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy", Locale.US);
try{
dateIn = (Date)formatter.parse(a);
}catch(ParseException e){
e.printStackTrace();
}
Log.d(TAG, "The server date is formated to : " + dateIn);
The dateIn is always null.
I want the to be able to do something like this
SimpleDateFormat sdf = new SimpleDateFormat("dd/mm/yyyy");
Date strDate = sdf.parse(valid_until);
if (new Date().after(strDate)) {
}

Use the following code...you will get the problem right.
Calendar calender = Calendar.getInstance();
SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
String timeStamp = formatter.format(calender.getTime());
Date strDate = formatter.parse(timeStamp);
String currentTimeStamp = formatter.format(new Date());
Date currentTime = formatter.parse(currentTimeStamp);
if (currentTime.after(strDate)) {
}

Don't know what you tried but this should work:
String a = connection.getHeaderField("Last-Modified");
Date date = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z", Locale.ENGLISH).parse(a);
This can help http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

The reason is that you are using the wrong date format for your formatter. If the date you receive looks like
"Wed, 29 Jan 2014 20:14:15 GMT"
Then you should use the following format
formatter = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z", Locale.US);

You should use the Calendar class and its subclass GregorianCalendar. For exampe, to get the month of your date:
Calendar cal = new GregorianCalendar();
cal.setTime(date);
cal.get(Calendar.MONTH);

How to handle the Time data from the Style just like "Wed Jun 20 11:01:05 +0800 2012"?

In my project ,I get json data from Server,there's a field named 'creat_at' in the json which style is like 'Wed Jun 20 11:01:05 +0800 2012'
How to change it to more easy-to-read style like '2012/06/20'?
(I have tried 'DateFormat.parse' but it dose not work:
new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy").parse(dateString)
cause
java.text.ParseException: Unparseable date: "Wed Jun 20 11:00:53 +0800 2012")

See SimpleDateFormat API
Date date = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy").parse(dateString);
String formattedDate = new SimpleDateFormat("yyyy/MM/dd").format(date);

You need to try SimpleDateFormat
SimpleDateFormat sdf = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy/MM/dd");
System.out.println(sdf2.format(sdf.parse("Wed Jun 20 11:01:05 +0800 2012")));
prints
2012/06/20
You may also need to set an approriate timezone.

convert string into java.util.date format in java

am having a string like this.
Thu Oct 07 11:31:50 IST 2010
I want to convert this into its exact date time format to store it in SQL.
Am familiar with so many string to date conversions like the following.
String dateString = "2001/03/09";
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/mm/dd");
Date convertedDate = dateFormat.parse(dateString);
But i need to convert a string like Thu Oct 07 11:31:50 IST 2010
into its Date format with timestamp.
Can anyone explain the proper way of converting this into its java.util.Date format.?

Try this:
SimpleDateFormat dateFormat = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy");
For future reference read up on the SimpleDateFormat class:
http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

Use this format -'EEE MMM dd HH:mm:ss z yyyy'
Date date = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy")
.parse("Thu Oct 07 11:31:50 IST 2010");
System.out.println(date);

Can't you do like below
String str = "Thu Oct 07 11:31:50 IST 2010";
SimpleDateFormat sdf = new SimpleDateFormat("E MMM dd hh:mm:ss 'IST' yyyy");
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy/MM/dd");
System.out.println(sdf2.format(sdf.parse(str)));