使用input以日期格式设置对象的值

Question

我希望能够将我的 SimpleDate 对象的值设置为我从输入中获得的日期。目前我收到错误

AgeClientFL.java:15: error: incompatible types dateBirth = sdf.parse(month +"+"+ day +"+"+ year); ^ required: SimpleDate found: Date 1 error

我该如何解决这个问题，还有什么问题吗？

import java.text.*;
import java.util.Date;
public class AgeClientFL {

public static void main(String [] args){

  int month, day, year;
  SimpleDateFormat sdf = new SimpleDateFormat(month+"+"+day+"+"+year);

  day = UtilsFL.readInt("Enter birth day: ",false); // String mode
  month = UtilsFL.readInt("Enter birth month: ",false);
  year = UtilsFL.readInt("Enter birth year: ",false);

  SimpleDate dateBirth = new SimpleDate();
  dateBirth = sdf.parse(month +"+"+ day +"+"+  year);

  day = UtilsFL.readInt("Enter todays day: ",true); // JOptionPane mode
  month = UtilsFL.readInt("Enter todays month: ",true);
  year = UtilsFL.readInt("Enter todays year: ",true);

  SimpleDate dateToday = new SimpleDate();


  SimpleDate milestone = new SimpleDate();

 }
}

如果需要，这是我的 SimpleDate class 文件。

import java.io.Serializable;        // for object I/O to file

//public class SimpleDate
public class SimpleDate implements Serializable

{
  private int month;
  private int day;
  private int year;

  /** default constructor
  *  sets month to 1, day to 1 and year to 2000
  */
  public SimpleDate( )
  {
    setDate( 1, 1, 2000 );
  }

  /** overloaded constructor
  *  @param mm    initial value for month
  *  @param dd    initial value for day
  *  @param yyyy  initial value for year
  *
  *  passes parameters to set methods
  */
  public SimpleDate( int mm, int dd, int yyyy )
  {
    setMonth( mm );
    setYear( yyyy );
    setDay( dd );
  }

  /* accessor methods */
  int getMonth( ) { return month; }
  int getDay( )   { return day; }
  int getYear( )  { return year; }

  /** mutator method */
  /** setMonth
  *  @param mm new value for month
  *  if mm is between 1 and 12, sets month to mm
  *  otherwise, sets month to 1
  */
  public void setMonth( int mm )
  {
    month = ( mm >= 1 && mm <= 12 ? mm : 1 );
  }

  /** setDay
  *  @param dd new value for day
  *  if dd is legal day for current month, sets day to dd
  *  otherwise, sets day to 1
  */
  public void setDay( int dd )
  {
    day = ( dd >= 1 && isValidDay( dd ) ? dd : 1 );
  }

  /** setYear
  *  @param yyyy new value for year
  *  sets year to yyyy
  */
  public void setYear( int yyyy )
  {
    year = yyyy;
  }

  /** sets date to the next day
  */
  public void nextDay( )
  {
     if ( ! isValidDay( ++day ) )
     {
         day = 1;
         if ( ++month > 12 )
         {
             month = 1;
             year++;
         }
     }
  }

  private boolean isValidDay( int newDay )
  {
     int [] daysInMonth = { 0, 31, 28, 31,
                                30, 31, 30,
                                31, 31, 30,
                               31, 30, 31 };

    if ( newDay > daysInMonth[month] )
    {
       if ( month == 2 && isLeapYear( ) && newDay == 29 )
          return true;
       else
          return false;
    }
    else
       return true;

  }

  private boolean isLeapYear( )
  {
     return !( year % 4 != 0
               ||( year % 100 == 0 && year % 400 != 0 ) );
  }


  /** setDate
  *  @param mm    new value for month
  *  @param dd    new value for day
  *  @param yyyy  new value for year
  *  passes parameters to setMonth, setDay, and setYear
  */
  public void setDate( int mm, int dd, int yyyy )
  {
    setYear( yyyy );  // set year first (could be leap year)
    setMonth( mm );   // set month next
    setDay( dd );     // set day
  }

  /** toString
  *  @return String
  *  returns date in mm/dd/yyyy format
  */
  public String toString( )
  {
    return month + "/" + day + "/" + year;
  }

  /** equals
  *  @param   d  Object to compare to this object
  *  @return  true if d is equal to this object
  *           false, otherwise
  */
  public boolean equals( Object d )
  {
    if ( !( d instanceof SimpleDate ) )
       return false;
    SimpleDate d1 = (SimpleDate)d;
    if ( month == d1.month
         && day == d1.day
         && year == d1.year )
      return true;
    else
      return false;
  }
}

Answer 1

您的变量 month、day、year 在调用 sdf 之前尚未初始化

int month, day, year;
SimpleDateFormat sdf = new SimpleDateFormat(month+"+"+day+"+"+year);

day = UtilsFL.readInt("Enter birth day: ",false); // String mode
month = UtilsFL.readInt("Enter birth month: ",false);
year = UtilsFL.readInt("Enter birth year: ",false);

编辑：现在，您收到错误消息，因为 dateBirth 不是 java.util.Date 的实例。您可以在 SimpleDate

中扩展 class java.util.date

使用input以日期格式设置对象的值

Use input to set the value of objects in a date format

java

format

date

input