java - 找不到符号: symbol: class SimpleDate location: class SimpleDateClient

Question

我正在使用 Netbeans。这些文件由于某种原因无法运行。我正在尝试导入 Netbeans 选项卡中的其他文件，但它们不起作用。如何使该应用程序也作为 main 方法运行 SimpleDateClient.java 。

这是SimpleDateClient.java

/* A client program to display SimpleDate object values
   Anderson, Franceschi
*/
package SimpleDateClient;

import java.awt.*;
import javax.swing.JFrame;


public class SimpleDateClient extends JFrame
{
  private String action = "";

  private int animationPause = 2; // 2 seconds between animations


  private SimpleDate dateObj; // declare SimpleDate object reference

  public void workWithDates( )
  {
    animate( "dateObj reference declared" );

    /***** Add your code here *****/
    /**** 1. Instantiate dateObj using an empty argument list  */
    dateObj = new SimpleDate();


    animate( "Instantiated dateObj - empty argument list" );

    /***** 2. Set the month to the month you were born */


    //animate( "Set month to birth month" );


    /***** 3. Set the day to the day of the month you were born */


    //animate( "Set day to birth day" );


    /***** 4. Set the year to the year you were born */


    //animate( "Set year to birth year" );


    /***** 5. Call the nextDay method */


    //animate( "Set the date to the next day" );


    /***** 6. Set the day to 32, an illegal value */


    //animate( "Set day to 32" );


    /***** 7. Set the month to 13, an illegal value */


    //animate( "Set month to 13" );


    /***** 8. Assign the value null to dateObj */


    //animate( "Set object reference to null" );


    /***** 9. Attempt to set the month to 1 */

  }

  public SimpleDateClient( )
  {
    super( "A SimpleDate Object" );

    setSize( 300, 300 );
    setVisible( true );
  }

  public void paint( Graphics g )
  {
    super.paint( g );

    // display action
    g.drawString( action, 50, 250 );

    // object reference
    int sX = 50, sY = 75;
    int boxL = 75, boxH = 20;
    g.drawRect( sX, sY, boxL, boxH );
    g.drawString( "dateObj", sX, sY - 10 );

    if ( dateObj != null )
       draw( g );
    else
      g.drawString( "null", sX + 15, sY + 15 );
  }

  public void draw( Graphics g )
  {
    int sX = 50, sY = 75;
    int boxL = 75, boxH = 20;

    // arrow
    g.drawLine( sX + boxL, sY + boxH / 2,
                sX + boxL + 25, sY + boxH / 2 );
    g.drawLine( sX + boxL + 25, sY + boxH / 2,
                sX + boxL + 25, sY + boxH * 2 );
    g.drawLine( sX + boxL + 25 - 5, sY + boxH * 2 - 5,
                sX + boxL + 25, sY + boxH * 2 );
    g.drawLine( sX + boxL + 25 + 5, sY + boxH * 2 - 5,
                sX + boxL + 25, sY + boxH * 2 );


    // month
    g.drawString( "month", sX + boxL - 50, sY + 2 * boxH + 15 );
    g.drawRect( sX + boxL, sY + 2 * boxH, boxL, boxH );
    g.drawString( Integer.toString( dateObj.getMonth( ) ),
                   sX + boxL + 5, sY + 2 * boxH + 15 );

    // day
    g.drawString( "day", sX + boxL - 50, sY + 3 * boxH + 15 );
    g.drawRect( sX + boxL, sY + 3 * boxH, boxL, boxH );
    g.drawString( Integer.toString( dateObj.getDay( ) ),
                  sX + boxL + 5, sY + 3 * boxH + 15 );

    // year
    g.drawString( "year", sX + boxL - 50, sY + 4 * boxH + 15 );
    g.drawRect( sX + boxL, sY + 4 * boxH, boxL, boxH );
    g.drawString( Integer.toString( dateObj.getYear( ) ),
                  sX + boxL + 5, sY + 4 * boxH + 15 );
  }

  public void animate( String a )
  {
    action = a;
    repaint( );
    Pause.wait( (double) animationPause );
  }

  public static void main( String [] args )
  {
    SimpleDateClient app = new SimpleDateClient( );
    app.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
    app.workWithDates( );
  }
}

这是SimpleDate.java

/* A simple date class
   Anderson, Franceschi
*/
package SimpleDateClient;


public class SimpleDate
{
  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;
  }
}

这是Pause.java

/* Pause class to pause applications
   Anderson, Franceschi
*/
package SimpleDateClient;

public class Pause
{
  public static void wait( double seconds )
  {
     try
     {
       Thread.sleep( (int) ( seconds * 1000 ) );
     }
     catch ( InterruptedException e )
     {
       e.printStackTrace( );
     }
  }
}

Answer 1

转到文件|新项目

从类别中选择Java，从项目中选择Java应用程序，单击下一步>

为项目命名并确保设置初始包/类

您的项目现在应该已经开始了。

现在可以选择是否将现有文件复制到项目中(在 Windows 下，您可以简单地从资源管理器复制文件并将其粘贴到项目中(在 src 节点下))，还是在项目中创建空类并简单地复制粘贴原始文件中的内容