Ticket Machine

  Ticket Machine adalah sebuah mesin seperti ATM, yang berfungsi melayani penjualan tiket kereta api dari satu tujuan ke tujuan yang lain. Di dalam Ticket Machine ada sebuah program atau perangkat lunak yang mengatur harga tiket di tiap tujuan, mengatur kembalian uang, dan juga mencetak receipt sebagai bukti pembelian tiket.

Berikut Source Code-nya:

  public class TicketMachine   
  {   
  // The price of a ticket from this machine.   
  private int price;   
  // The amount of money entered by a customer so far.   
  private int balance;   
  // The total amount of money collected by this machine.   
  private int total;   
  /**   
  * Create a machine that issues tickets of the given price.   
  * Note that the price must be greater than zero, and there   
  * are no checks to ensure this.   
  */   
  public TicketMachine(int ticketCost)   
  {   
  price = ticketCost;   
  balance = 0;   
  total = 0;   
  }   
  /**   
  * Return the price of a ticket.   
  */   
  public int getPrice()   
  {   
  return price;   
  }   
  /**   
  * Return the amount of money already inserted for the   
  * next ticket.   
  */   
  public int getBalance()   
  {   
   return balance;   
  }   
  /**   
  * Receive an amount of money in cents from a customer.   
  */   
  public void insertMoney(int amount)   
  {   
   balance = balance + amount;   
  }   
  /**   
  * Print a ticket.   
  * Update the total collected and   
  * reduce the balance to zero.   
  */   
  public void printTicket()   
  {   
   // Simulate the printing of a ticket.   
   System.out.println("##################");   
   System.out.println("# The BlueJ Line");   
   System.out.println("# Ticket");   
   System.out.println("# " + price + " cents.");   
   System.out.println("##################");   
   System.out.println();   
   // Update the total collected with the balance.   
   total = total + balance;   
   // Clear the balance.   
   balance = 0;   
  }   
 }  

Output:

Chapter 8 Classes and Objects

8.1

source code:

 /**   
  * Program Kelas Time1   
  * Deklarasi kelas Time1 mengelola waktu dalam format 24 jam    
  * Nama file : Time1.java   
  */   
  public class Time1   
  {   
   private int hour;    
   private int minute;    
   private int second;    
   //set a new time value using universal time;   
   //throw an exception if the hour, minute, or second is invalid   
   public void setTime( int h, int m, int s)   
   {   
    if ( (h >= 0 && h < 24) && (m >= 0 && m < 60) && (s >= 0 && s < 60))   
    {   
     hour = h;   
     minute = m;   
     second = s;   
    }   
    else    
     throw new IllegalArgumentException(   
      "hour, minute and/or second was out of range");   
   }//end method setTime   
   //convert to String in universal-time format (HH:MM:SS)   
   public String toUniversalString()   
   {   
    return String.format ("%02d:%02d:%02d", hour, minute, second);   
   }//end method toUniversalString   
   //convert to String in standart-time format (H:MM:SS AM or PM)   
   public String toString ()   
   {   
    return String.format ("%d:%02d:%02d %s",    
     ( ( hour == 0 || hour == 12) ? 12 : hour % 12),   
     minute, second, (hour < 12 ? "AM" : "PM") );   
   }//end method toString   
  }   

8.2

source code:

  /**   
  * Program Kelas Time1Test   
  * Objek Time1 digunakan dalam aplikasi   
  * nama file : Time1Test.java   
  */   
 public class Time1Test   
  {   
   public static void main( String[] args )   
   {   
    Time1 time = new Time1();   
    System.out.print( "The initial universal time is: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print( "The initial standard time is: ");   
    System.out.println(time.toString() );   
    System.out.println();   
    time.setTime( 13, 27, 6);   
    System.out.print( "Universal time after setTime is: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print("Standard time after setTime is: ");   
    System.out.println( time.toString() );   
    System.out.println();   
    try   
    {   
     time.setTime( 99, 99 , 99 );   
    }   
    catch ( IllegalArgumentException e )   
    {   
     System.out.printf( "Exception: %s\n\n", e.getMessage() );   
    }   
    System.out.println( "After attempting invalid settings:");   
    System.out.print( "Universal time: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print("Standard time: ");   
    System.out.println( time.toString() );   
   }   
  }   

Output:

8.3

source code:

 /**   
  * Program Kelas MemberAccessTest   
  * Anggota kelas private Time1 tidak dapat diakses   
  * Nama file : MemberAccessTest.java   
  */   
 public class MemberAccessTest  
 {  
   public static void main(String[] args)  
   {  
     Time1 time = new Time1();  
     time.hour = 7; //error: has private access  
     time.minute = 15; //error: has private access  
     time.second = 30; //error: has private access  
   }  
 }  

8.4

source code:

 public class Time1Test   
  {   
   public static void main( String[] args )   
   {   
    Time1 time = new Time1();   
    System.out.print( "The initial universal time is: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print( "The initial standard time is: ");   
    System.out.println(time.toString() );   
    System.out.println();   
    time.setTime( 13, 27, 6);   
    System.out.print( "Universal time after setTime is: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print("Standard time after setTime is: ");   
    System.out.println( time.toString() );   
    System.out.println();   
    try   
    {   
     time.setTime( 99, 99 , 99 );   
    }   
    catch ( IllegalArgumentException e )   
    {   
     System.out.printf( "Exception: %s\n\n", e.getMessage() );   
    }   
    System.out.println( "After attempting invalid settings:");   
    System.out.print( "Universal time: ");   
    System.out.println(time.toUniversalString() );   
    System.out.print("Standard time: ");   
    System.out.println( time.toString() );   
   }   
  }   

Output:

8.5

source code:

 /**   
  * Program Kelas Time2   
  * Deklarasi kelas Time2 dengan konstuktor overload   
  * Nama file : Time2.java   
  */  
 public class Time2  
 {  
   private int hour;  
   private int minute;  
   private int second;  
   public Time2()  
   {  
     this( 0, 0, 0 );  
   }  
   public Time2( int h )  
   {  
     this( h, 0, 0 );  
   }  
   public Time2( int h, int m )  
   {  
     this( h, m, 0 );  
   }  
   public Time2( int h, int m, int s )  
   {  
     setTime( h, m, s );  
   }  
   public Time2( Time2 time )  
   {  
     this( time.getHour(), time.getMinute(), time.getSecond() );  
   }  
   public void setTime( int h, int m, int s )  
   {  
     setHour( h );  
     setMinute( m );  
     setSecond( s );  
   }  
   public void setHour( int h )  
   {  
     if ( h >= 0 && h < 24 )  
       hour = h;  
     else  
       throw new IllegalArgumentException( "hour must be 0-23" );  
   }  
   public void setMinute( int m )  
   {  
     if ( m >= 0 && m < 60 )  
       minute = m;  
     else  
       throw new IllegalArgumentException( "minute must be 0-59" );  
   }  
   public void setSecond( int s )  
   {  
     if ( s >= 0 && s < 60 )  
       second = ( ( s >= 0 && s < 60 ) ? s : 0 );  
     else  
       throw new IllegalArgumentException( "second must be 0-59" );  
   }  
   public int getHour()  
   {  
     return hour;  
   }  
   public int getMinute()  
   {  
     return minute;  
   }  
   public int getSecond()  
   {  
     return second;  
   }  
   public String toUniversalString()  
   {  
     return String.format(  
       "%02d:%02d:%02d", getHour(), getMinute(), getSecond() );  
   }  
   public String toString()  
   {  
     return String.format( "%d:%02d:%02d %s",  
       ((getHour() == 0 || getHour() == 12) ? 12 : getHour() % 12 ),  
         getMinute(), getSecond(), ( getHour() < 12 ? "AM" : "PM" ) );  
   }  
 }  

8.6

source code:

 /**   
  * Program Kelas Time2Test   
  * Konstruktor overload digunakan untuk menginisialisasi objek Time2   
  * Nama file : Time2Test.java   
  */   
 public class Time2Test  
 {  
   public static void main(String[] args)  
   {  
     Time2 t1 = new Time2();  
     Time2 t2 = new Time2( 2 );  
     Time2 t3 = new Time2( 21, 34 );  
     Time2 t4 = new Time2( 12, 25, 42 );  
     Time2 t5 = new Time2( t4 );  
     System.out.println( "Constructed with:" );  
     System.out.println( "t1: all arguments defaulted" );  
     System.out.printf( " %s\n", t1.toUniversalString() );  
     System.out.printf( " %s\n", t1.toString() );  
     System.out.println(  
       "t2: hour specified; minute and second defaulted" );  
     System.out.printf( " %s\n", t2.toUniversalString() );  
     System.out.printf( " %s\n", t2.toString() );  
     System.out.println(  
       "t3: hour and minute specified; second defaulted" );  
     System.out.printf( " %s\n", t3.toUniversalString() );  
     System.out.printf( " %s\n", t3.toString() );  
     System.out.println( "t4: hour, minute and second specified" );  
     System.out.printf( " %s\n", t4.toUniversalString() );  
     System.out.printf( " %s\n", t4.toString() );  
     System.out.println( "t5: Time2 object t4 specified" );  
     System.out.printf( " %s\n", t5.toUniversalString() );  
     System.out.printf( " %s\n", t5.toString() );  
     try  
     {  
       Time2 t6 = new Time2( 27, 74, 99 );  
     }  
     catch ( IllegalArgumentException e )  
     {  
       System.out.printf( "\nException while initializing t6: %s\n",  
       e.getMessage() );  
     }  
   }  
  }  

Output: