Time2 t1 = new Time2();              // 00:00:00
      Time2 t2 = new Time2( 2 );           // 02:00:00
      Time2 t3 = new Time2( 21, 34 );      // 21:34:00
      Time2 t4 = new Time2( 12, 25, 42 );  // 12:25:42
      Time2 t5 = new Time2( 27, 74, 99 );  // 00:00:00
      Time2 t6 = new Time2( t4 );          // 12:25:42

// Fig. 8.5: Time2.java
// Time2 class declaration with overloaded constructors.  
import java.text.DecimalFormat;  

public class Time2 {
   private int hour;    // 0 - 23
   private int minute;  // 0 - 59
   private int second;  // 0 - 59

   // Time2 constructor initializes each instance variable to zero;
   // ensures that Time object starts in a consistent state
   public Time2() 
   { 
      this( 0, 0, 0 ); // invoke Time2 constructor with three arguments
   }

   // Time2 constructor: hour supplied, minute and second defaulted to 0
   public Time2( int h ) 
   { 
      this( h, 0, 0 ); // invoke Time2 constructor with three arguments
   }

   // Time2 constructor: hour and minute supplied, second defaulted to 0
   public Time2( int h, int m ) 
   { 
      this( h, m, 0 ); // invoke Time2 constructor with three arguments
   }

   // Time2 constructor: hour, minute and second supplied
   public Time2( int h, int m, int s ) 
   { 
      setTime( h, m, s ); // invoke setTime to validate time
   }

   // Time2 constructor: another Time2 object supplied
   public Time2( Time2 time )
   {
      // invoke Time2 constructor with three arguments
      this( time.hour, time.minute, time.second );
   }

   // set a new time value using universal time; perform 
   // validity checks on data; set invalid values to zero
   public void setTime( int h, int m, int s )
   {
      hour = ( ( h >= 0 && h < 24 ) ? h : 0 );
      minute = ( ( m >= 0 && m < 60 ) ? m : 0 );
      second = ( ( s >= 0 && s < 60 ) ? s : 0 );
   }

   // convert to String in universal-time format
   public String toUniversalString()
   {
      DecimalFormat twoDigits = new DecimalFormat( "00" );

      return twoDigits.format( hour ) + ":" +
         twoDigits.format( minute ) + ":" + twoDigits.format( second );
   }

   // convert to String in standard-time format
   public String toStandardString()
   {
      DecimalFormat twoDigits = new DecimalFormat( "00" );
      
      return ( (hour == 12 || hour == 0) ? 12 : hour % 12 ) + ":" + 
         twoDigits.format( minute ) + ":" + twoDigits.format( second ) +
         ( hour < 12 ? " AM" : " PM" );
   }

} // end class Time2

// Fig. 8.6: TimeTest3.java
// Overloaded constructors used to initialize Time2 objects.
import javax.swing.*;

public class TimeTest3 {

   public static void main( String args[] )
   {
      Time2 t1 = new Time2();              // 00:00:00
      Time2 t2 = new Time2( 2 );           // 02:00:00
      Time2 t3 = new Time2( 21, 34 );      // 21:34:00
      Time2 t4 = new Time2( 12, 25, 42 );  // 12:25:42
      Time2 t5 = new Time2( 27, 74, 99 );  // 00:00:00
      Time2 t6 = new Time2( t4 );          // 12:25:42

      String output = "Constructed with: " +
         "\nt1: all arguments defaulted" +
         "\n      " + t1.toUniversalString() +
         "\n      " + t1.toStandardString();

      output += "\nt2: hour specified; minute and second defaulted" +
         "\n      " + t2.toUniversalString() +
         "\n      " + t2.toStandardString();

      output += "\nt3: hour and minute specified; second defaulted" +
         "\n      " + t3.toUniversalString() +
         "\n      " + t3.toStandardString();

      output += "\nt4: hour, minute and second specified" +
         "\n      " + t4.toUniversalString() +
         "\n      " + t4.toStandardString();

      output += "\nt5: all invalid values specified" +
         "\n      " + t5.toUniversalString() +
         "\n      " + t5.toStandardString();

      output += "\nt6: Time2 object t4 specified" +
         "\n      " + t6.toUniversalString() +
         "\n      " + t6.toStandardString();

      JOptionPane.showMessageDialog( null, output,
         "Overloaded Constructors", JOptionPane.INFORMATION_MESSAGE );

      System.exit( 0 );

   } // end main

} // end class TimeTest3