Improving my date parsing

Question

Hi, I have two methods that I use together to parse dates from raw text files:
I format the date with this:
public static String formatDate(String date){
          String[] parts = null;
          String yr = "";
          String mn = "";
          String dy = "";
          String pad = "0";
          if(date.contains("/")){
               parts = date.split("/");
               if(parts.length==3){
                    if(parts[0].length()==4){
                         yr = parts[0];
                         mn = parts[1];
                         dy = parts[2];
                    }else if(parts[2].length()==4){
                         yr = parts[2];
                         mn = parts[0];
                         dy = parts[1];
          }else if(date.contains("-")){
               parts = date.split("-");
               if(parts.length==3){
                    if(parts[0].length()==4){
                         yr = parts[0];
                         mn = parts[1];
                         dy = parts[2];
                    }else if(parts[2].length()==4){
                         yr = parts[2];
                         mn = parts[0];
                         dy = parts[1];
          if(dy.length()==1){
               dy = pad+dy;
          if(mn.length()==1){
               mn = pad+mn;
          return yr+mn+dy;
     }Then I parse the formatted date with this:
public static synchronized Date asOfDate(String str) {
          //System.out.println("here it is"+str);
          Date dd = null;
          Date ddd = null;
          if(str.contains("/")){
               SimpleDateFormat sdf2 = new SimpleDateFormat("MMddyyyy");
          str = str.replace("/", "");
          String yr = str.substring(0, 4);
          String mn = str.substring(4, 6);
          String d = str.substring(6, 8);
          System.out.println(yr);
          System.out.println(mn);
          System.out.println(d);
          String dddd = mn+ d + yr;
          //System.out.println(dddd);
          try {
               dd = sdf2.parse(dddd);
          } catch (ParseException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
          }else{
               SimpleDateFormat sdf2 = new SimpleDateFormat("yyyyMMdd");
               try {
                    dd= sdf2.parse(str);
               } catch (ParseException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
          return dd;
     }My question is even if I try to prevent the exceptions by checking the String length before formatting, I still keep getting Exceptions. Im just trying to only run these two methods of the String looks good. What am I doing wrong?
I try to do this:
if((string.length()==8))
string date = TradeHelper.formatDate(temp.substring(84, 92);
//then
TradeHelper.asOfDate(date);Im trying for this:
If the date ="", don't try anything.
but this doesn't seem to work.
java.text.ParseException: Unparseable date: ""
     at java.text.DateFormat.parse(DateFormat.java:335)
     at helper.TradeHelper.asOfDate(TradeHelper.java:213)
     at dazl.DAZLClass.parseFile(DAZLClass.java:127)
     at dazl.DAZLClass.main(DAZLClass.java:48)I know this is stupid, but I'm a little buried right now and could use the extra eyes.

Answer 1

How about sometime like the following to parse dates with / in them. You don't have to remove them first.
public static Date asOfDate(String dateStr) {
  String format;
  switch(dateStr.indexOf('/')) {
    case 4: format = "yyyy/MM/dd"; break;
    case 2: format = "MM/dd/yyyy"; break;
    default: throw new IllegalArgumentException("Unknown format for "+dateStr);
  SimpleDateFormat sdf = new SimpleDateFormat(format);
  return sdf.parse(dateStr);
}