Java determines whether a string conforms to the YYYYMMDD date format

Java determines whether a string conforms to the YYYYMMDD date format

Code:

    /*** Determine if the format of the parameter is a valid date string in the format "YYYYMMDD" **/       Public Static Booleanisvaliddate (String str) {Try {              if(str! =NULL&&!str.equals ("")) {                  if(str.length () = = 8) {                      //leap Year Flag                    BooleanIsleapyear =false; String Year= str.substring (0, 4); String Month= Str.substring (4, 6); String Day= Str.substring (6, 8); intVyear =Integer.parseint (year); //Judging whether the year is legal                    if(Vyear < 1900 | | vyear > 2200) {                          return false; }                      //determine if a leap year                    if(vyear% 4 = = 0 && vyear%! = 0 | | vyear% 400 = 0) {isleapyear=true; }                      //Judging the month//1. Judging the month                    if(Month.startswith ("0") ) {String units4month= Month.substring (1, 2); intVunits4month =Integer.parseint (Units4month); if(Vunits4month = = 0) {                              return false; }                          if(Vunits4month = = 2) {                              //get the number of days in February                            intVdays4february =Integer.parseint (day); if(isleapyear) {if(Vdays4february > 29)                                      return false; } Else {                                  if(Vdays4february > 28)                                      return false; }                          }                      } Else {                          //2. Determine if a month that is not 0 is legal                        intVmonth =Integer.parseint (month); if(Vmonth! = && Vmonth! = && Vmonth! = 12) {                              return false; }                      }                      //Judging Date//1. Date of Judgment                    if(Day.startswith ("0") ) {String units4day= Day.substring (1, 2); intVunits4day =Integer.parseint (Units4day); if(Vunits4day = = 0) {                              return false; }                      } Else {                          //2. Determine if the date of the non-0 is legal                        intVDay =Integer.parseint (day); if(VDay < | | VDay > 31) {                              return false; }                      }                      return true; } Else {                      return false; }              } Else {                  return false; }          } Catch(Exception e) {//TODO auto-generated Catch blockE.printstacktrace (); return false; }      }  

Java determines whether a string conforms to the YYYYMMDD date format