Question

public static void main(String[] args) {
       // TODO Auto-generated method stub
       Scanner keyboard = new Scanner(System.in);
       System.out.println("Enter a date in the format month/day/year");
       String date = keyboard.nextLine();
       //Make a copy
       String dateCopy = date;
      
       //Extract the values
       //start with month
       //indexOf() is used to find the index of a specified character in a givenString
       int workingIndex = date.indexOf("/");
      
       //substring(int beginIndex, int endIndex)
       //return strings substring
       String sM = date.substring(0,workingIndex);
       //convert string to integer
       int m = Integer.parseInt(sM);
      
       //move to day
       date = date.substring(workingIndex+1);
       workingIndex = date.indexOf("/");
       String sD = date.substring(0,workingIndex);
       int d = Integer.parseInt(sD);
      
       //move to year
       date = date.substring(workingIndex+1);
       int year = Integer.parseInt(date);
      
       //check the valid date
       //a valid month must be from 1 to 12
       if(m<1 || m>12)
       {
           System.out.println(dateCopy + "is invalid! The month must be between 1 and 12.");
       }
       //Leap year
       //February has 28 days except on leap years (29).
       else if (m==2)
       {
           if(d == 29)
       {
               //Leap years are years that are divisible by 4.
               //but not divisible by 100 unless also divisible by 400.
              
               if(!(year%4==0 && (year%100!=0 || year%400 == 0)))
               {
                   System.out.println(dateCopy + " is invalid! The date given is not a leap year.");
               }
               else
               {
                   System.out.println(dateCopy + " is a valid date!");
               }
           }//Normal year
           else if (d<1 || d>28)
           {
               System.out.println(dateCopy + " is invalid! The day is wrong for this month. Must be between 1 and 28.");
           }
           else
           {
               System.out.println(dateCopy + " is a valid date!");
           }
       }
       //April, June, September, and November have 30 days
       else if(m==4 && (d<1 || d>30) || m==6 && (d<1 || d>30) || m==9 && (d<1 || d>30) || m==11 && (d<1 || d>30))
       {
           System.out.println(dateCopy + " is invalid! The day is wrong for this month. Must be between 1 and 30.");
       }
       else if((m==1 || m==3 || m==5 || m==7 || m==8 || m==10 || m==12) && (d<1 || d>31))
       {
           System.out.println(dateCopy + " is invalid! The day is wrong for this month. Must be between 1 and 31.");
       }
       else
       {
           System.out.println(" is a valid date!");
       }
       }
   }

Looking for the flowchart for this code. It determines the validity of a user inputted birth date entered in the format in the code.

Answer 1

The Flowchart is very big.

Please find all the conditions slowly.

I have made it easy for you to understand.