编写一个程序以提示添加到当前日期的天数并打印新日期以及今天的日期

Question

打印出今天的日期。格式应该是MM/DD/YYYY。月份应该从1开始，而不是0。提示读取要添加到当前日期的天数并打印新日期。

谁来帮我一下

    import java.util.calendar;
    import java.util.Date;
    import java.util.GregorianCalendar;
    public class JavaDateAdd {
     public static void main(String[] args) {
    Date date = new Date();
    System.out.println("Today's Date Is: " + (now.get(Calendar.MONTH) + 1) +         "/" + now.get(Calendar.DATE) + "/" + now.get(Calendar.YEAR));
    System.out.print("Number of Days You Want To ADD: ");
    int AddDays = in.nextInt();
    Date newDate = addDays(date,AddDays);
        System.out.println("Java Date after adding "+AddDays+" days: "+(now.get(Calendar.MONTH) + 1) + "/" + now.get(Calendar.DATE) + "/" + now.get(Calendar.YEAR));

     }
    }`

Answer 1

您可以修改代码以接受天数，并接受您的日期格式。

public static void main(String[] args) {

               Calendar cal = Calendar.getInstance();
               // print current date
               System.out.println("The current date is : " + cal.getTime());
               // add 20 days to the calendar
               cal.add(Calendar.DATE, 20);
               System.out.println("20 days later: " + cal.getTime());
               Date tommrrow = cal.getTime();
               SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yy");
               String date = formatter.format(tommrrow);
               System.out.println("20 days in dd-MM-yy: " + date);
}

Answer 2

使用SimpleDateFormat格式化日期:SimpleDateFormat是一个具体的类，用于以语言环境敏感的方式格式化和解析日期。SimpleDateFormat允许您首先选择任何用户定义的日期时间格式化模式。例如:

import java.util.*;
import java.text.*;
public class HelloWorld {
public static void main(String args[]) {
    Date dNow = new Date( );
    SimpleDateFormat sdf = 
    new SimpleDateFormat ("MM/dd/yyyy ");
    System.out.println("Current Date: " + sdf.format(dNow));
    Calendar c = Calendar.getInstance();
    c.setTime(new Date()); // Now use today date.
    c.add(Calendar.DATE, 35); // Adding 35 days
    String output = sdf.format(c.getTime());
    System.out.println("New Date: "+ output);
 }
}

这将产生以下结果:

Current Date: 09/24/2015                                                                                                                               
New Date: 10/29/2015 

Answer 3

打印出今天的日期。格式应该是MM/DD/YYYY。月份应该从1开始，而不是0。

从DateTimeFormatter开始，例如:

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MM/dd/yyyy");
System.out.println("Today is " + formatter.format(LocalDateTime.now()));

提示读取要添加到当前日期的天数

首先看一下扫描，例如:

    Scanner scanner = new Scanner(System.in);
    System.out.print("How many days to add: ");
    int days = scanner.nextInt();

和打印新的日期。

首先看一下Java 8的Date Time API，例如:

LocalDateTime ldt = LocalDateTime.now();
ldt = ldt.plusDays(days);
System.out.println(formatter.format(ldt));