Your regex matches day first and then month (DD/MM/YYYY), while your inputs start with month and then day (MM/DD/YYYY).

Moreover, your dates must be followed by a comma to be matched (the (?:,) part).

This one should suit your needs:

(0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)\d\d

Diagram by Debuggex.

3 Problems :

1) You are trying to parse date with format dd/MM/YYYY where as your regex has format MM/dd/YYYY.

2) You forgot to increment count in the while loop.

3) The (?:,) part at the end of the regex is useless.

This codes works on my computer :

private static String[] getDate(String desc) {
  int count=0;
  String[] allMatches = new String[2];
  Matcher m = Pattern.compile("(0[1-9]|[12][0-9]|3[01])[- /.](0[1-9]|1[012])[- /.](19|20)\\d\\d").matcher(desc);
  while (m.find()) {
    allMatches[count] = m.group();
    count++;
  }
  return allMatches;
}

Test :

public static void main(String[] args) throws Exception{
  String[] dates = getDate("coming from the 25/11/2009 to the 30/11/2009");

  System.out.println(dates[0]);
  System.out.println(dates[1]);

}

Output :

25/11/2009
30/11/2009

A date pattern recognition algorithm to not only identify date pattern but also fetches probable date in Java date format. This algorithm is very fast and lightweight. The processing time is linear and all dates are identified in a single pass. Algorithm resolves date using tree traverse mechanism. Tree data structures are custom created to build supported date, time and month patterns.

The algorithm also acknowledges multiple space characters in between Date literals. E.g. DD DD DD and DD DD DD are considered as valid dates.

Following date-patterns are considered as valid and are identifiable using this algorithm.

dd MM(MM) yy(yy) yy(yy) MM(MM) dd MM(MM) dd yy(yy)

Where M is month literal is alphabet format like Jan or January

Allowed delimiters between dates are '/', '\', ' ', ',', '|', '-', ' '

It also recognizes trailing time pattern in following format hh(24):mm:ss.SSS am / pm hh(24):mm:ss am / pm hh(24):mm:ss am / pm

Resolution time is linear, no pattern matching or brute force is used. This algorithm is based on tree traversal and returns back, the list of date with following three components - date string identified in the text - converted & formatted date string - SimpleDateFormat

Using date string and the format string, users are free to convert the string into objects based on their requirements.

The algorithm library is available at maven central.

<dependency>
    <groupId>net.rationalminds</groupId>
    <artifactId>DateParser</artifactId>
    <version>0.3.0</version>
</dependency>

The sample code to use this is below.

import java.util.List;  
 import net.rationalminds.LocalDateModel;  
 import net.rationalminds.Parser;  
 public class Test {  
   public static void main(String[] args) throws Exception {  
        Parser parser=new Parser();  
        List<LocalDateModel> dates=parser.parse("Identified date :'2015-January-10 18:00:01.704', converted");  
        System.out.println(dates);  
   }  
 }  

Output: [LocalDateModel{originalText=2015-january-10 18:00:01.704, dateTimeString=2015-1-10 18:00:01.704, conDateFormat=yyyy-MM-dd HH:mm:ss.SSS, start=18, end=46}]

Detailed blog at http://coffeefromme.blogspot.com/2015/10/how-to-extract-date-object-from-given.html

The complete source is available on GitHub at https://github.com/vbhavsingh/DateParser

LocalTime.parse instead of regex

Regex can be overkill for such a problem.

You could just split the string on SPACE character, and attempt to parse each element as a LocalDate. If the parse fails, move on to the next element.

String input = "coming from the 11/25/2009 to the 11/30/2009" ;
String[] elements = input.split( " " ) ; 
DateTimeFormatter f = DateTimeFormatter.ofPattern( "MM/dd/uuuu" ) ;
List<LocalDate> dates = new ArrayList<>() ;
for( String element : elements ) {
    try {
        LocalDate ld = LocalDate.parse( element , f ) ;
        dates.add( ld ) ;
    } catch ( DateTimeParseException e ) {
        // Ignore the exception. Move on to next element.
    }
}
System.out.println( "dates: " + dates ) ;

See this code run live at IdeOne.com.

dates: [2009-11-25, 2009-11-30]