Question

我正在尝试创建一个以两个日期作为参数的程序，并返回日期是否在当前周，但我对isDateInCurrentWeek的调用存在问题。当我尝试编译程序时，收到错误说

requestHoliday.java:16: isDateInCurrentWeek(java.util.GregorianCalendar) in requestHoliday cannot be applied to (java.util.Calendar)
      if (isDateInCurrentWeek(startDate) && isDateInCurrentWeek(endDate));

import java.util.*;
import java.text.*;

public class hols {
   public static void main( String[] args ) {
      DateFormat df = new SimpleDateFormat("dd MM yyyy");
      Date start = df.parse(args[0]);
      Date end = df.parse(args[1]);
      Calendar startDate = new GregorianCalendar();
      Calendar endDate = new GregorianCalendar();
      startDate.setTime(start);
      endDate.setTime(end);
      if( isDateInCurrentWeek( startDate ) && isDateInCurrentWeek( endDate ));
         System.out.println( "Date is in current week!" );
   }

   public static boolean isDateInCurrentWeek(GregorianCalendar date) {
      Calendar currentCalendar = GregorianCalendar.getInstance();
      int week = currentCalendar.get(Calendar.WEEK_OF_YEAR);
      int year = currentCalendar.get(Calendar.YEAR);
      Calendar targetCalendar = GregorianCalendar.getInstance();
      targetCalendar = date;
      int targetWeek = targetCalendar.get(Calendar.WEEK_OF_YEAR);
      int targetYear = targetCalendar.get(Calendar.YEAR);
      return week == targetWeek && year == targetYear;
   }
}

不太确定问题是什么，因为该方法将Gregoriancalendar作为输入，并且两个日期是格里高利历日历格式。有人知道吗？

Answer 1

;末尾有if，请将其删除...

阳历是一个日历，而不是相反。如果抽象和通用方法适合您的需要，请将签名更改为使用日历。如果可能，最好使用合同而不是What does it mean to "program to an interface"?中解释的实现（感谢Luiggi）。

hols id不是good class name。 Hols可能会更好......

此代码效果很好：

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

public class Hols {
   public static void main( String[] args ) throws ParseException {
      DateFormat df = new SimpleDateFormat("dd MM yyyy");
      Date start = df.parse( args[0] );
      Date end   = df.parse( args[1] );
      Calendar startDate = new GregorianCalendar();
      Calendar endDate = new GregorianCalendar();
      startDate.setTime(start);
      endDate.setTime(end);
      if( isDateInCurrentWeek( startDate ) && isDateInCurrentWeek( endDate ))
         System.out.println( "Date is in current week!" );
      else
         System.out.println( "Date is NOT in current week!" );
   }

   public static boolean isDateInCurrentWeek( Calendar date ) {
      Calendar currentCalendar = Calendar.getInstance();
      int week = currentCalendar.get(Calendar.WEEK_OF_YEAR);
      int year = currentCalendar.get(Calendar.YEAR);
      Calendar targetCalendar = Calendar.getInstance();
      targetCalendar = date;
      int targetWeek = targetCalendar.get(Calendar.WEEK_OF_YEAR);
      int targetYear = targetCalendar.get(Calendar.YEAR);
      return week == targetWeek && year == targetYear;
   }
}

Answer 2

当您致电isDateInCurrentWeek时，您传入的变量的类型为Calendar。将它们声明为GregorianCalendar。

如果您不需要任何GregorianCalendar具体内容，请在isDateInCurrentWeek更改方法签名以接受Calendar。

格里高利历法

2 个答案: