java - 为什么我的程序没有打印出我想要的内容？

Question

当我运行我的代码时，我的输出是这样的

----jGRASP exec: java AgeClientFL

Enter birth day: 5 Enter birth month: 5 Enter birth year: 5 Birth:5/5/5

Today: 1/1/0 Age: 0

Michaels Birth: 5/7/1995 Milestone: 5/7/2016Age at Milestone: 0

----jGRASP: operation complete.

对于今天，我输入了 10/10/10，我希望它以 10/10/10 的形式出现，但它以 1/1/0 的形式出现。对于第一个 age，我想得到 5，但得到了 0。Age at Milestone 应该是 21 而不是 0。

我的代码的哪些部分导致了这些不正确的打印输出，我该如何解决？这是我正在使用的代码的第 1 部分。

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

public static void main(String [] args){

  int month, day, year, age;
  
  
  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(month,day,year);
  
  System.out.println("Birth: " + dateBirth);
  
  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(month,day,year);
  
  System.out.println("Today: " + dateToday);
  
  age = UtilsFL.getAge(dateBirth,dateToday);
  System.out.println("Age: " + age);
  
  month = 5;
  day = 7;
  year = 2016;
  SimpleDate milestone = new SimpleDate(month,day,year);
  month=5;
  day=7;
  year=1995;
  SimpleDate bdMilestone = new SimpleDate(month,day,year);
  int mAge;
  mAge = UtilsFL.getAge(bdMilestone, milestone);
  System.out.println("Michaels Birth: " + bdMilestone);
  System.out.println("Milestone: " + milestone);
  System.out.println("Age at Milestone: " + mAge);
  
}
}

这是第二部分。

import java.util.GregorianCalendar;
import java.util.Date;
import javax.swing.JOptionPane;
import java.util.Scanner;
import java.util.Calendar;    

public class UtilsFL {


public static int readInt(String prompt,boolean guiFlag) {

    if (guiFlag==false){
    Scanner input = new Scanner(System.in);
    int data;
    
    System.out.print(prompt);
    data = input.nextInt();
    
    return data;
    }
    else if (guiFlag==true) {
    int data;
    data = Integer.parseInt(JOptionPane.showInputDialog(prompt));
    }
    return 0;
    
  }      
    



public static SimpleDate today() {


    Calendar todayCal = Calendar.getInstance();
    SimpleDate todayDate = new SimpleDate();
    

    todayDate.setDate(todayCal.get(Calendar.MONTH) + 1, 
                      todayCal.get(Calendar.DATE),
                      todayCal.get(Calendar.YEAR));
    return todayDate;
}


public static int getAge(SimpleDate dateBd) {
    int age;
    SimpleDate dateToday = today();
    
    
    age = getAge(dateBd, dateToday);  
    return age;
    
} 

public static int getAge(SimpleDate dateBd, SimpleDate dateRef) {
  Calendar cal = new GregorianCalendar ();
  Calendar now = new GregorianCalendar();
    int rAge = now.get(Calendar.YEAR) - cal.get(Calendar.YEAR);
 if((cal.get(Calendar.MONTH) > now.get(Calendar.MONTH)
   || (cal.get(Calendar.MONTH) == now.get(Calendar.MONTH)
   && cal.get(Calendar.DAY_OF_MONTH) > now.get(Calendar.DAY_OF_MONTH))))
 {
    rAge--;
 }
    return rAge;
    
    
}
        
}

我认为这可能是我代码第二部分底部的 public static int getAge 的问题。但我不确定，我不知道如何修复它。

这是我以前的一些代码中引用的 SimpleDate 类的代码。

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

在您的方法 UtilsFL#readInt 中，您忘记在 GUI 模式下返回 data:

public static int readInt(String prompt, boolean guiFlag) {
    if (guiFlag == false) {
        Scanner input = new Scanner(System.in);
        int data;

        System.out.print(prompt);
        data = input.nextInt();

        return data;
    } else if (guiFlag == true) {
        int data;
        data = Integer.parseInt(JOptionPane.showInputDialog(prompt));
        // HERE: you need to return data
    }
    return 0;
}

所以在 GUI 模式下你总是得到 0。你可能还想简化 == true, == false, ...