public class Validator {
               private static final String NEW_LINE = "<BR>";
    private static final String DATE_FORMAT = "yyy-MMM-dd";
    SimpleDateFormat SDF = new SimpleDateFormat(DATE_FORMAT);

                private List errorList = new ArrayList();

    // Defualt Constructor
    public Validator () {
        errorList = new ArrayList();
    }

/****************************************************************************
 *Description of getErrors Method:Returns the list.of error Messages
 *

 *

****************************************************************************/
 public List getErrors() {
   return errorList;
 }

/****************************************************************************
 *Description of printErrors Method:this method calls getErrors method
which
 *                                  gives List of Errors then they are
printed
 *                                  on Server Window
 *

******************************************************************************/

 public void printErrors() {
   List l = getErrors();
   if (l.size() == 0) {
     log.debug("There are no errors!!");
   } else {
     Iterator i = l.iterator();
     while (i.hasNext()) {
       log.debug(i.next());
     }
   }
 }

/****************************************************************************
  *Description of validate method:This method is used for validating
String
  *                               values which are Mandetory
  *                               Typically the developer should get
the value
  *                               from the container and then call
this method
  *                               to check if it present of not
(i.e.it is null
  *                               or blank.)if it finds value null
then it calls
  *                               formatAndAdd(String message) method

  *
  *@Param:
- *   value - Value in String format
  *   Message - If the value is not present then this message is added
to the
  *             errorList.
  *

****************************************************************************/
 public void validate (String value, String message) {

   if (value == null  || value.equals("") ) {
     formatAndAdd(message);
   }

 }

/****************************************************************************
  *Description of validateDate method:This method is used for
validating Date
  *                                   which is in String Format
  *                                   Typically the developer should
check get
  *                                   the value from the containerand
then call
  *                                   this method to check if the date
is in
  *                                   correct format or not.
  *
  *@Param:
  *   value - Date as a String Object
  *   Message - If the Date is not in correct format then this message
is added
  *             to the errorList.
  *

*****************************************************************************/
 public void validateDate (String value, String message) {

   try {
     Date d = SDF.parse(value);
     System.out.println("This is the Date: " + d);
   } catch (Exception e) {
     formatAndAdd(message);
   }

 }

/******************************************************************************
*Description of formatAndAdd method:this method is called by other
methods of
*                                   the same class for  formating the
message
*                                   and adding it errorList when
method finds
*                                   any Validation error in input
Parameter
*
*@Param
*   message:message to be added to error List
*

******************************************************************************/
 private void formatAndAdd(String message) {
   StringBuffer sb = new StringBuffer(NEW_LINE);
   sb.append(message);
   sb.append(NEW_LINE);
   if (!errorList.contains(message)) {
     errorList.add(sb.toString());
   }
 }

}

hope this will help

For validating the date, use SimpleDateFormat's parse method.
You should also set lenient to false.  An exception will be thrown if
it doesn't parse.

try {
 DateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
 // this is very important, otherwise 31-09-2005 would parse as
01-10-2005
 sdf.setLenient(false);
 java.util.Date dt = sdf.parse("01-01-2006");
}
catch (ParseException pe) {
 // invalid date format
}

To insert into DB2, get a database connection and prepare a statement,
and like you were guessing, use PreparedStatement.setDate(int pos,
java.sql.Date date);