问题

I am getting a parsing exception while I am trying the following code:

    String date=\"Sat Jun 01 12:53:10 IST 2013\";
    SimpleDateFormat sdf=new SimpleDateFormat(\"MMM d, yyyy HH:mm:ss\");
    Date currentdate;
    currentdate=sdf.parse(date);
    System.out.println(currentdate);

Exception:

Exception in thread \"main\" java.text.ParseException: Unparseable date: \"Sat Jun 01 12:53:10 IST 2013\" at com.ibm.icu.text.DateFormat.parse(DateFormat.java:510)

Input: Sat Jun 01 12:53:10 IST 2013

Expected output: Jun 01,2013 12:53:10

How to solve this?

回答1:

Your pattern does not correspond to the input string at all... It is not surprising that it does not work. This would probably work better:

SimpleDateFormat sdf = new SimpleDateFormat("EE MMM dd HH:mm:ss z yyyy",
                                            Locale.ENGLISH);

Then to print with your required format you need a second SimpleDateFormat:

Date parsedDate = sdf.parse(date);
SimpleDateFormat print = new SimpleDateFormat("MMM d, yyyy HH:mm:ss");
System.out.println(print.format(parsedDate));

Notes:

you should include the locale as if your locale is not English, the day name might not be recognised
IST is ambiguous and can lead to problems so you should use the proper time zone name if possible in your input.

回答2:

        String date="Sat Jun 01 12:53:10 IST 2013";
        SimpleDateFormat sdf=new SimpleDateFormat("E MMM dd HH:mm:ss z yyyy");
        Date currentdate=sdf.parse(date);
        SimpleDateFormat sdf2=new SimpleDateFormat("MMM dd,yyyy HH:mm:ss");
        System.out.println(sdf2.format(currentdate));

回答3:

Pattern is wrong

    String date="Sat Jun 01 12:53:10 IST 2013";
    SimpleDateFormat sdf=new SimpleDateFormat("E MMM dd hh:mm:ss Z yyyy");
    Date currentdate;
    currentdate=sdf.parse(date);
    System.out.println(currentdate);

回答4:

Update your format to:

SimpleDateFormat sdf=new SimpleDateFormat("E MMM dd hh:mm:ss Z yyyy");

回答5:

Your formatting pattern fails to match the input string, as noted by other Answers.
Your input format is terrible.
You are using troublesome old date-time classes that were supplanted years ago by the java.time classes.

ISO 8601

Instead a format such as yours, use ISO 8601 standard formats for exchanging date-time values as text.

The java.time classes use the standard ISO 8601 formats by default when parsing/generating strings.

Proper time zone name

Specify a proper time zone name in the format of continent/region, such as America/Montreal, Africa/Casablanca, or Pacific/Auckland. Never use the 3-4 letter abbreviation such as EST or IST as they are not true time zones, not standardized, and not even unique(!).

Your IST could mean Iceland Standard Time, India Standard Time, Ireland Standard Time, or others. The java.time classes are left to merely guessing, as there is no logical solution to this ambiguity.

java.time

The modern approach uses the java.time classes.

Define a formatting pattern to match your input strings.

String input = "Sat Jun 01 12:53:10 IST 2013";
DateTimeFormatter f = DateTimeFormatter.ofPattern( "EEE MMM dd HH:mm:ss z uuuu" , Locale.US );
ZonedDateTime zdt = ZonedDateTime.parse( input , f );

zdt.toString(): 2013-06-01T12:53:10Z[Atlantic/Reykjavik]

If your input was not intended for Iceland, you should pre-parse the string to adjust to a proper time zone name. For example, if you are certain the input was intended for India, change IST to Asia/Kolkata.

String input = "Sat Jun 01 12:53:10 IST 2013".replace( "IST" , "Asia/Kolkata" );
DateTimeFormatter f = DateTimeFormatter.ofPattern( "EEE MMM dd HH:mm:ss z uuuu" , Locale.US );
ZonedDateTime zdt = ZonedDateTime.parse( input , f );

zdt.toString(): 2013-06-01T12:53:10+05:30[Asia/Kolkata]

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.

Where to obtain the java.time classes?

Java SE 8, Java SE 9, Java SE 10, and later
- Built-in.
- Part of the standard Java API with a bundled implementation.
- Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
- Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
- Later versions of Android bundle implementations of the java.time classes.
- For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

回答6:

I found simple solution to get current date without any parsing error.

Calendar calendar;
calendar = Calendar.getInstance();
String customDate = "" + calendar.get(Calendar.YEAR) + "-" + (calendar.get(Calendar.MONTH) + 1) + "-" + calendar.get(Calendar.DAY_OF_MONTH);

回答7:

String date="Sat Jun 01 12:53:10 IST 2013";

SimpleDateFormat sdf=new SimpleDateFormat("MMM d, yyyy HH:mm:ss");

This patterns does not tally with your input String which occurs the exception.

You need to use following pattern to get the work done.

E MMM dd HH:mm:ss z yyyy

Following code will help you to skip the exception.

SimpleDateFormat is used.

    String date="Sat Jun 01 12:53:10 IST 2013"; // Input String

    SimpleDateFormat simpleDateFormat=new SimpleDateFormat("E MMM dd HH:mm:ss z yyyy"); // Existing Pattern

    Date currentdate=simpleDateFormat.parse(date); // Returns Date Format,

    SimpleDateFormat simpleDateFormat1=new SimpleDateFormat("MMM dd,yyyy HH:mm:ss"); // New Pattern

    System.out.println(simpleDateFormat1.format(currentdate)); // Format given String to new pattern

    // outputs: Jun 01,2013 12:53:10

回答8:

Check your Pattern (DD-MMM-YYYY) and the input for the parse("29-11-2018") method. Input to the parse method should follow : DD-MMM-YYYY i,e. 21-AUG-2019

In My Code:

String pattern = "DD-MMM-YYYY";
SimpleDateFormat simpleDateFormat = new SimpleDateFormat(pattern);

    try {
        startDate = simpleDateFormat.parse("29-11-2018");// here no pattern match 
        endDate = simpleDateFormat.parse("28-AUG-2019");// Ok 
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

回答9:

I needed to add a ParsePosition expression to the parse method of class SimpleDateFormat:

simpledateformat.parse(mydatestring, new ParsePosition(0));

来源：https://stackoverflow.com/questions/16871367/java-text-parseexception-unparseable-date

标签

java

simpledateformat

parseexception