java - 尝试在 Java 中获取日期格式 - 从单独的函数调用

Question

我正在尝试根据用户输入的月、日和年检索日期格式。应该从一个函数和另一个函数中的逻辑调用它。当我运行代码时，问题会运行，但日期不会输出，即使它返回到 getArrivalDate 方法也是如此。有什么想法吗？

代码:

import java.time.format.DateTimeFormatter;
import java.time.format.FormatStyle;
import java.util.Scanner;
import java.time.LocalDateTime;
import java.time.Month;
import java.text.NumberFormat;
import java.time.LocalDate;

public class Reserve {

public static void main(String[] args) {


    System.out.println("Enter the requested input");
    System.out.println();

    //Call Arrival Date Method
    getArrivalDate();
}

 public static void getArrivalDate() {
    // create a Scanner object
        Scanner sc = new Scanner(System.in);
        String choice = "y";

        while (choice.equalsIgnoreCase("y")) {

            System.out.print("month (1-12): ");
            int month = sc.nextInt();
            System.out.print("day (1-31):  ");
            int day = sc.nextInt();
            System.out.print("year: ");
            int year = sc.nextInt();  

         setArrivalDate(choice);
          //Users choice
            choice = sc.nextLine();
        }
 } //End getArrivalDate

 public static String setArrivalDate(String arrivalDate1) {

        String month = "no month";
        int day = 0;
        int year = 0;

        switch(month) {
        case "1":
            month = "January";
        break;

        case "2":
            month = "February";
        break;

        case "3":
            month = "March";
        break;

        case "4":
            month = "April";
        break;

        case "5":
            month = "May";
        break;

        case "6":
            month = "June";
        break;

        case "7":
            month = "July";
        break;

        case "8":
            month = "August";
        break;

        case "9":
            month = "September";
        break;

        case "10":
            month = "October";
        break;

        case "11":
            month = "November";
        break;

        case "12":
            month = "December";
        break;
        }

 return arrivalDate1 = "Arrival Date: " + month + day + year;
      return arrivalDate1;  
}


}

Answer 1

你至少需要打印出返回值

并且您正在传递choice，它始终只是“y”...如果您想显示实际日期，请首先传递每个值

System.out.println(setArrivalDate(year, month, day));

这并不是真正正确的 returnarrivalDate1 = "Arrival Date: "...。您不必返回变量，只需返回字符串，例如 return "Arrival Date:"...

我建议学习 DateFormatter 类，而不是 switch case