Android parse String to Date - unknown pattern character 'X'

Question

I have Service fetch date string from web and then I want to pare it to Date object. But somehow application crashes. This is my string that I\'m parsi

Answer 1

Remove "XXX" from

DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");

and everything would work fine.

Go through the list of symbols that can be used inside a SimpleDateFormat constructor. Although the documentation shows the "XXX" format, this doesn't work on Android and will throw an IllegalArgumentException.

Probably you are looking for "yyyy-MM-dd'T'HH:mm:ss.SSSZ"

Change your code to

DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS"); 

or

DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ"); // if timezone is required

Answer 2

You are using the wrong date formatter.

Use this instead: DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");

I think that android in contrast with Java 7 uses Z (as in Java 6) for timezones and not X. So, use this for your date formats.

Answer 3

Based on idea from Alexander K, I optimize it and support parsing from and to UTC timezone format like 1970-01-01T00:00:00Z, to make all behaviour exactly same as yyyy-MM-dd'T'HH:mm:ssXXX.

public class IsoSimpleDateFormatBeforeNougat extends SimpleDateFormat {

    public IsoSimpleDateFormatBeforeNougat() {
        super("yyyy-MM-dd'T'HH:mm:ssZ");
    }

    public IsoSimpleDateFormatBeforeNougat(Locale locale) {
        super("yyyy-MM-dd'T'HH:mm:ssZ", locale);
    }

    public IsoSimpleDateFormatBeforeNougat(DateFormatSymbols formatSymbols) {
        super("yyyy-MM-dd'T'HH:mm:ssZ", formatSymbols);
    }

    @Override
    public Date parse(String text, ParsePosition pos) {
        if (text.endsWith("Z")) {
            return super.parse(text.substring(0, text.length() - 1) + "+0000", pos);
        }
        if (text.length() > 3 && text.substring(text.length() - 3, text.length() - 2).equals(":")) {
            text = text.substring(0, text.length() - 3) + text.substring(text.length() - 2);
        }
        return super.parse(text, pos);
    }

    @Override
    public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition pos) {
        StringBuffer rfcFormat = super.format(date, toAppendTo, pos);
        if (rfcFormat.substring(rfcFormat.length() - 5).equals("+0000")) {
            return rfcFormat.replace(rfcFormat.length() - 5, rfcFormat.length(), "Z");
        }
        return rfcFormat.insert(rfcFormat.length() - 2, ":");
    }
}

Test code:

@Test
public void test() throws ParseException {
    //SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");
    SimpleDateFormat sdf = new IsoSimpleDateFormatBeforeNougat();
    sdf.setTimeZone(TimeZone.getTimeZone("GMT+8"));

    assertEquals("1970-01-01T08:00:00+08:00", sdf.format(new Date(0)));
    assertEquals(0L, sdf.parse("1970-01-01T08:00:00+08:00").getTime());

    sdf.setTimeZone(TimeZone.getTimeZone("GMT+0"));

    assertEquals("1970-01-01T00:00:00Z", sdf.format(new Date(0)));
    assertEquals(0L, sdf.parse("1970-01-01T00:00:00Z").getTime());
}

Answer 4

Use a SimpleDateFormat to produce a properly formatted String output:

SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
simpleDateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));

String formattedNow = simpleDateFormat.format(new Date(System.currentTimeMillis()));

Output : 2018-02-27T07:36:47.686Z

Answer 5

The following class can be used to convert the string to date when pattern doesn't aware of it.

    import java.text.SimpleDateFormat;
    import java.util.Arrays;
    import java.util.Date;
    import java.util.List;

/**
 * StringToDateFormater is a concrete class for formatting and parsing dates in a locale-sensitive manner. It allows for
 * formatting (date → text), parsing (text → date), and normalization.
 * 
 * This class is mainly used for convert the date from string. It should be used only when date pattern doesn't aware of
 * it. 
 *
 */
public class StringToDateFormater extends SimpleDateFormat {

    private static final List<String> DATE_SUPPORTED_FORMAT_LIST = Arrays.asList("yyyyMMddHHmmss", "yyyyMMddHHmm",
            "yyyyMMddHHmm", "yyyyMMddHH", "yyyyMMdd", "yyyyMMddHHmmssSS");

    /**
     * 
     */
    private static final long serialVersionUID = -1732857502488169225L;

    /**
     * @param pattern
     */
    public StringToDateFormater() {
    }

    @Override
    public Date parse(String source) {
        Date date = null;

        SimpleDateFormat dateFormat = null;
        for (String format : DATE_SUPPORTED_FORMAT_LIST) {
            dateFormat = new SimpleDateFormat(format);
            try {
                return dateFormat.parse(source);
            } catch (Exception exception) {

            }

        }

        return date;
    }
}

Answer 6

The error is saying that simpleDateFormat does not recognize the character X. If you are looking for milliseconds it is represented with the character S.

DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");