Question

如果不是周末或假日（存储在txt文件中），我试图创建一个添加到变量的程序。我的代码说这是一个周末，即使它不是，我很困惑。什么都有帮助谢谢！

代码

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.concurrent.TimeUnit;

public class Main {

  public static void main(String[] args) {

    int day = 0;
    while (true) {

      // Gets current date
      Calendar cal = Calendar.getInstance();
      cal.add(cal.DATE, day);
      SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy");
      String formatted = format.format(cal.getTime());

      System.out.println("\nDate: " + formatted);

      try {
        // If its Saturday or Sunday
        if (cal.DAY_OF_WEEK == Calendar.SATURDAY || cal.DAY_OF_WEEK == Calendar.SUNDAY) {
          System.out.println("Weekend");
          System.exit(0);
        }   
        else {
          // Opens the dates.txt
          BufferedReader reader = new BufferedReader(new FileReader("dates.txt"));
          String line  = reader.readLine(); // The current line

          // Loops through the file until end
          while (line != null) {            
            if (line == formatted)// If holiday is current day {
              System.out.println("Holiday");
              System.exit(0);
            }
            line = reader.readLine();   // Goes to the next line
          }
          System.out.println("School");
          day += 1;
        }
      }    
      catch(FileNotFoundException e){}
      catch(IOException e){}

      try {
        TimeUnit.SECONDS.sleep(2);
      } catch (InterruptedException e1) {
        System.out.println("ERROR: Sleep Failed");
      }
      day ++;
    }
  }
}

Answer 1

这是错误的：

if (cal.DAY_OF_WEEK == Calendar.SATURDAY || cal.DAY_OF_WEEK == Calendar.SUNDAY)

cal.DAY_OF_WEEK 不日历设置的星期几，它是一个与get方法一起使用的常量一周的当天：

if (cal.get(Calendar.DAY_OF_WEEK) == Calendar.SATURDAY || cal.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY)

Answer 2

您以错误的方式使用属性：

  if (cal.get(Calendar.Day_OF_WEEK) == Calendar.SATURDAY || cal.get(Calendar.Day_OF_WEEK) == Calendar.SUNDAY){
                System.out.println("Weekend");
                System.exit(0);
            }

请参阅Java doc：

DAY_OF_WEEK获取和设置的字段编号，表示日期周。

Java日历无法显示正确的信息

2 个答案: