您可以在try/catch块中解析每个日期及其数字，并按如下方式递增计数器:

public static void main(String[] args) {
     String[] dates = new String[]{"car","bench","01/04/2019", "01/13/2019", "29/02/200s"};
     System.out.println(validate(dates));
}
private static int validate(String[] dates){
     int count = 0;
     DateFormat format = new SimpleDateFormat("dd/MM/yyyy");
     format.setLenient(false);
     for(String date : dates) {
          try {
               format.parse(date);
               String[] dateParts = date.split("/");
               for(String str : dateParts)
                    Integer.parseInt(str);
               if(dateParts.length!=3 || dateParts[0].length()!=2 || dateParts[1].length()!=2 || dateParts[2].length()!=4)
                    throw new Exception();
               count++;
          } catch (Exception e) {
               System.out.println("Date " + date + " is not valid");
          }
     }
     return count;
}

输出:

Date car is not valid
Date bench is not valid
Date 01/13/2019 is not valid
Date 29/02/200s is not valid
1

编辑:根据OLE的评论和这篇帖子，最好使用更精确的库:

public static void main(String[] args) {
     String[] dates = new String[]{"car","bench","01/04/2019", "01/13/2019", "29/02/200s"};
     System.out.println(validate(dates));
}
private static int validate(String[] dates){
     int count = 0;
     for(String date : dates) {
          try {
               String[] dateParts = date.split("/");
               if(dateParts.length==3 && isDateValid(Integer.parseInt(dateParts[2]), Integer.parseInt(dateParts[1]), Integer.parseInt(dateParts[0])))
                    count++;
               else
                    throw new Exception();
          } catch (Exception e) {
               System.out.println("Date " + date + " is not valid");
          }
     }
     return count;
}
private static boolean isDateValid(int year, int month, int day) {
     boolean dateIsValid = true;
     try {
          LocalDate.of(year, month, day);
     } catch (DateTimeException e) {
          dateIsValid = false;
     }
     return dateIsValid;
}