[UnrealEd]

I'm trying to convert a date-string, like "14-05-2007", to a Date object using the SimpleDateFormat class and the SimpleDateFormat.parse method.

There are a few ways the date-string can be formated, and i need to get the correct correspondig date. This is the code i'm using atm:

package com.upjlib.audio.tags.utils;
 
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;
 
import com.upjlib.audio.tags.InvalidTagException;
 
public class DateFormat {
 
    public GregorianCalendar date = null;
 
    public DateFormat() {
 
    }
 
    public DateFormat(String format) throws InvalidTagException {
        Date date = null;
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy-MM-dd'T'HH:mm:ss");
            } catch (ParseException e) {
            }
        }
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy-MM-dd'T'HH:mm");
            } catch (ParseException e) {
            }
        }
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy-MM-dd'T'HH");
            } catch (ParseException e) {
            }
        }
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy-MM-dd");
            } catch (ParseException e) {
            }
        }
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy-MM");
            } catch (ParseException e) {
            }
        }
        if (date == null) {
            try {
                date = tryFormat(format, "yyyy");
            } catch (ParseException e) {
            }
        }
 
        if (date == null) {
            throw new InvalidTagException("Invalid date format found: "
                    + format);
        } else {
            this.date = new GregorianCalendar();
            this.date.setTime(date);
        }
    }
 
    private Date tryFormat(String format, String pattern) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
        return sdf.parse(format);
    }
 
    public GregorianCalendar getDate() {
        return date;
    }
 
    public static void main(String[] args) {
        try {
            DateFormat df = new DateFormat("12/");
            System.out.println(df.getDate().getTime());
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }
} 

When running this script, with an invalid date-string "12/", it still parses it as a valid date-string instead of throwing an InvalidTagException or ParseException. I found out that the last date-pattern ("yyyy") matches anything that is passed on to the SimpleDateFormat.parse method as long as it's not an empty String.

So now my question is: is there a way to get an exact match of the entered date-string and the date-pattern? It says in the manual that the SimpleDateFormat.parse method doesn't always use all characters of the entered date-string, so....

Thanks in advance

[King Coder]

I'm not sure I understand what you're doing with the DateFormat constructor. Wouldn't it be easier and more efficient to do it this way (plus it seems to parse correctly):

Code:

import java.text.*;
import java.util.*;

public class DateFormat 
{

    private Date d;
    public DateFormat(String format, String parseDate)
   {
        try
        {
           SimpleDateFormat sdf = new SimpleDateFormat(format);
           d = sdf.parse(parseDate);
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
            d = null;
        }
    }

    public Date getDate() 
    {
        return d;
    }

    public static void main(String[] args) 
    {
        try 
        {
            DateFormat df = new DateFormat("yyyy-MM-dd'T'HH:mm:ss", "12/");
            System.out.println(df.getDate().getTime());
        } 
         catch (Exception e) 
         {
            System.out.println(e.getMessage());
        }
    }
}

You provide the format in the constructor, is that a problem?

[King Coder]

Of course, you couldn't shorten it even more by just creating a date through simpledateformat directly.

[UnrealEd]

The thing i want to do is get a Date object from a date-string. I get the date-string from a file, and there are different date-formats (yyyy, yyyy-MM, yyyy-MM-dd, etc.). So the problem is that the string i read from the file can be any of these formats. That's why i try to match the date-string against a certain format.

So if i enter a date-string like this one: "2007-05-15T15:57:23", it would return a Date object with 2007 as year, 05 as month, 15 as day, 15 as hour, 57 as minutes and 23 as seconds. But if i enter "2007-05-15" it would only return a Date object with 2007 as year, 05 as month and 15 as day.

Atm, when i enter "12/" which is an invalid date-pattern, it still matches the "yyyy" pattern, so that's basically my problem.

If you know an easier way to accomplish this, do let me know. I could use regex though.

I tried using your code, exactly as you posted it, but it didn't seem to work. it prints:

java.text.ParseException: Unparseable date: "12/"

Thanx for looking into it

[King Coder]

Originally Posted by UnrealEd

The thing i want to do is get a Date object from a date-string. I get the date-string from a file, and there are different date-formats (yyyy, yyyy-MM, yyyy-MM-dd, etc.). So the problem is that the string i read from the file can be any of these formats. That's why i try to match the date-string against a certain format.

So if i enter a date-string like this one: "2007-05-15T15:57:23", it would return a Date object with 2007 as year, 05 as month, 15 as day, 15 as hour, 57 as minutes and 23 as seconds. But if i enter "2007-05-15" it would only return a Date object with 2007 as year, 05 as month and 15 as day.

Atm, when i enter "12/" which is an invalid date-pattern, it still matches the "yyyy" pattern, so that's basically my problem.

If you know an easier way to accomplish this, do let me know. I could use regex though.

I tried using your code, exactly as you posted it, but it didn't seem to work. it prints:


Thanx for looking into it

I thought you wanted a parse exception to occur when 12/ is entered? I'll take a look at matching the strings exactly a little latter tomorrow....