java - 要求 Java 返回到特定语句

Question

我目前正在写一个程序，我需要程序返回一个特定的语句。我试过做一个循环，但它非常复杂。有没有更简单的方法？

(如果用户选择是，则重新运行程序。如果否，则结束程序。)

public class CA_1316855_P3 {

    public static void main(String[] args) {
        //Variables
        char Destination, JobType, Currency;
        double ExchangeRate = 0, Maximum = 0, Ammount = 0, NewExchangeRate, NewCharge;
        int Charge = 0;
        String ID, JobTitle = null, Name, Nationality, Mobile, CurrencyTitle = null, DestinationTitle = null;
        int BLANK = 0;
        int Count_u = 0;
        int Count_y = 0;
        int Count_p = 0;
        int Count_i = 0;

        //Destination
        while (BLANK == 0) {
            System.out.println("\t\t\t          ---------------------------------------------");
            System.out.println("\t\t\t\t\t Welcome to Transferring System");
            System.out.println("\t\t\t          ---------------------------------------------");
            System.out.println(" Press u for Transferring to USA \n Press y for transferring to Yemen \n Press p for Transferring to Pakistan");
            System.out.println(" Press i for Transferring to India \n Press n for new destination country");
            System.out.print("Enter the Choice: ");
            Scanner input1 = new Scanner(System.in);
            Destination = input1.next().charAt(0);
            while (Destination != '*')
                if (Destination == 'u' ||
                    Destination == 'U' ||
                    Destination == 'y' ||
                    Destination == 'Y' ||
                    Destination == 'p' ||
                    Destination == 'P' ||
                    Destination == 'i' ||
                    Destination == 'I' ||
                    Destination == 'n' ||
                    Destination == 'N') {

                    if (Destination == 'u' || Destination == 'U') {
                        ExchangeRate = 0.267;
                        Count_u++;
                        DestinationTitle = "United States";
                    } else if (Destination == 'y' || Destination == 'Y') {
                        DestinationTitle = "Yemen";
                        Count_y++;
                        ExchangeRate = 57.300;
                    } else if (Destination == 'p' || Destination == 'P') {
                        DestinationTitle = "Pakistan";
                        Count_p++;
                        ExchangeRate = 28.367;
                    } else if (Destination == 'i' || Destination == 'I') {
                        DestinationTitle = "India";
                        Count_i++;
                        ExchangeRate = 17.417;
                    } else if (Destination == 'n' || Destination == 'N') {
                        System.out.print("Enter the name of destination country: ");
                        Scanner input3 = new Scanner(System.in);
                        String NewDestinationName = input3.next();
                        System.out.print("Enter the Exchange Rate between SAR and " + NewDestinationName + " Currency: ");
                        Scanner input4 = new Scanner(System.in);
                        NewExchangeRate = input4.nextDouble();
                    }
                    break;
                } else {
                    System.out.print("***Wrong Selection !!*** \nEnter choice again:");
                    Destination = input1.next().charAt(0);
                }


            //Job Type
            System.out.println("\t\t------------\n\t\t  Job Type \n\t\t------------ ");
            System.out.println(" Press 0 for ordinary employee \n Press 1 for academician employee \n Press 2 for medical employee");
            System.out.print("Enter the Choice: ");
            Scanner input2 = new Scanner(System.in);
            JobType = input2.next().charAt(0);
            while (JobType != '*') {
                if (JobType == '0' || JobType == '1' || JobType == '2') {
                    if (JobType == '0') {
                        JobTitle = "Ordinary";
                        Maximum = 15000;
                    } else if (JobType == '1') {
                        JobTitle = "Academician";
                        Maximum = 50000;
                    } else if (JobType == '2') {
                        JobTitle = "Medical";
                        Maximum = 80000;
                    }
                    break;
                } else {
                    System.out.println("***Wrong Selection !!*** \nEnter choice again:");
                    JobType = input2.next().charAt(0);
                }
            }


            //Currency

            System.out.println("\t\t------------\n\tType of Currency to be received \n\t\t------------ ");
            System.out.println(" Press S for Saudi Riyal \n Press L for local Currency");
            System.out.print("Enter The Choice: ");
            Scanner input5 = new Scanner(System.in);
            Currency = input5.next().charAt(0);
            while (Currency != '*') {
                if (Currency == 's' || Currency == 'l' || Currency == 'S' || Currency == 'L') {
                    break;
                } else {
                    System.out.println("***Wrong Selection !!*** \nEnter choice again:");
                    Currency = input5.next().charAt(0);
                }
            }

            System.out.print("Enter the amount to be transferred: ");
            Scanner input6 = new Scanner(System.in);
            Ammount = input6.nextDouble();

            if (Ammount > Maximum) {

                System.exit(0);
            } else if (Ammount <= 10000 && (Destination == 'u' || Destination == 'U') && Currency == 's') {
                Charge = 40;
                ExchangeRate = 1;
                CurrencyTitle = "SAR";
            } else if (Ammount < 10000 && (Destination == 'u' || Destination == 'U') && Currency == 'l') {
                Charge = 25;
                CurrencyTitle = "USD";
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'u' || Destination == 'U') && Currency == 's') {
                Charge = 100;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'u' || Destination == 'U') && Currency == 'l') {
                Charge = 70;
                CurrencyTitle = "USD";
            } else if (Ammount < 10000 && (Destination == 'y' || Destination == 'Y') && Currency == 's') {
                Charge = 20;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount < 10000 && (Destination == 'y' || Destination == 'Y') && Currency == 'l') {
                Charge = 10;
                CurrencyTitle = "YER";
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'y' || Destination == 'Y') && Currency == 's') {
                Charge = 50;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'y' || Destination == 'Y') && Currency == 'l') {
                Charge = 30;
                CurrencyTitle = "YER";
            } else if (Ammount < 10000 && (Destination == 'p' || Destination == 'P') && Currency == 's') {
                Charge = 30;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount < 10000 && (Destination == 'p' || Destination == 'P') && Currency == 'l') {
                Charge = 20;
                CurrencyTitle = "PKR";
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'p' || Destination == 'P') && Currency == 's') {
                Charge = 80;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'p' || Destination == 'P') && Currency == 'l') {
                Charge = 55;
                CurrencyTitle = "PKR";
            } else if (Ammount < 10000 && (Destination == 'i' || Destination == 'I') && Currency == 's') {
                Charge = 25;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount < 10000 && (Destination == 'i' || Destination == 'I') && Currency == 'l') {
                Charge = 15;
                CurrencyTitle = "INR";
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'i' || Destination == 'I') && Currency == 's') {
                Charge = 70;
                CurrencyTitle = "SAR";
                ExchangeRate = 1;
            } else if (Ammount > 10000 && Ammount < 80000 && (Destination == 'i' || Destination == 'I') && Currency == 'l') {
                Charge = 50;
                CurrencyTitle = "INR";
            } else if (Destination == 'n' || Destination == 'N') {
                System.out.print("Enter the charges: ");
                Scanner input9 = new Scanner(System.in);
                NewCharge = input9.nextDouble();
                System.out.print("Enter the currency: ");
                Scanner input12 = new Scanner(System.in);
                CurrencyTitle = input12.next();
            }

            System.out.print("Enter the ID Number: ");
            Scanner input7 = new Scanner(System.in);
            ID = input7.next();
            System.out.print("Enter the Name: ");
            Scanner input8 = new Scanner(System.in);
            Name = input8.next();
            System.out.print("Enter the Nationality: ");
            Scanner input10 = new Scanner(System.in);
            Nationality = input10.next();
            System.out.print("Enter the Mobile Number: ");
            Scanner input11 = new Scanner(System.in);
            Mobile = input11.next();

            //Printing the Bill
            System.out.println("\n\n\n\n\t\t\t\t------------------------------------------");
            System.out.println("\t\t\t\t\t The current Transaction");
            System.out.println("\t\t\t\t------------------------------------------");
            System.out.println("Sender: " + Name + "\t\t\t Destination: " + DestinationTitle);
            System.out.println("Job Type: " + JobTitle + "\t\t\t Nationality: " + Nationality + "\t\t Mobile: " + Mobile);
            System.out.println("\t\t\t The Original Ammount: " + Ammount);
            System.out.println("\t\t\t The Recieved Ammount: " + Ammount * ExchangeRate);
            System.out.println("\t\t\t The Total Amount Cost: " + ((int) (Ammount) + (Charge)));
            int reply = JOptionPane.showConfirmDialog(null, "Would you like to do another transaction ?", "Question.", JOptionPane.YES_NO_OPTION);
            if (reply == JOptionPane.YES_OPTION) {
                continue;
            } else if (reply == JOptionPane.NO_OPTION && Count_u >= 1 && Count_y >= 1 && Count_p >= 1 && Count_i >= 1) {
                System.exit(0);
            } else {
                JOptionPane.showMessageDialog(null, "You need to perform at least one transaction for each country.");
                continue;
            }

        }
    }
}

Answer 1

试试extract method pattern .这使得这个困惑可读。

解压后，只复制粘贴重要的部分到stackoverflow求助，实现回跳会容易很多。

public class CA_1316855_P3 {

    public static void main(String[] args) {

        int reply;

        do {

            businessLogic();

            reply = askUser();

        } while (userWantRepeat(reply));

    }
}