// Filename HeterogenousMonitors.java.
// Contains an indeterminate number of WarningCounter 
// or RoomMonitor instances with actions to write and 
// read them from a stream. 
//
// Written for JFL Book Chapter 12.
// Fintan Culwin, V 0.1, Jan 1997. 

import Counters.WarningCounter;
import Counters.RoomMonitor;
import java.io.*;
import java.util.Random;
import java.util.Date;


class HeterogeneousMonitors { 

private  Random generator = new Random( new Date().getTime()); 
private  WarningCounter theMonitors[];

    
   public HeterogeneousMonitors(){
   
   int numberOfMonitors = 2 + 
               (int) (generator.nextDouble() * 5.0);
   int index; 
   int anotherIndex;
   int numberOfOccurrences; 
                    
      theMonitors = new WarningCounter[ numberOfMonitors];
      for ( index =0; index < numberOfMonitors; index++) {
         if (generator.nextDouble() > 0.5) {     
            theMonitors[ index] = new WarningCounter();
         } else { 
            theMonitors[ index] = new  RoomMonitor();
         } // End if.   
         numberOfOccurrences = 10 + 
                       (int) (generator.nextDouble() * 20.0);
         for ( anotherIndex =0; 
               anotherIndex < numberOfOccurrences;
               anotherIndex++) {                      
            if ( (generator.nextDouble() > 0.5)              &&
                 (theMonitors[ index].numberCountedIs() > 0) ){
               theMonitors[ index].unCount();  
            } else { 
               theMonitors[ index].count(); 
            } // End if.
         } // End for.                         
      } // End for.  
   } // End HomogenousMonitors constructor.


   public void resetMonitors() {
    
   int index;        
      for ( index =0; index < theMonitors.length; index++) {
         if (generator.nextDouble() > 0.5) {     
            theMonitors[ index] = new WarningCounter();
         } else { 
            theMonitors[ index] = new  RoomMonitor();
         } // End if.   
      } // End for.
   } // End resetMonitors.


   public void writeMonitors( String filename) { 

   int index;     
   DataOutputStream theStream;

       try { 
          theStream = new DataOutputStream( 
                              new FileOutputStream( filename));
          theStream.writeInt( theMonitors.length);                    
          for ( index =0; index < theMonitors.length; index++) {
             theStream.writeUTF( theMonitors[ index].getClass().getName());
             theMonitors[ index].write( theStream);           
          } // End for.  
          theStream.close();
       } catch ( java.io.IOException exception) { 
          System.out.println( "Exception thrown on writing ... abending");
          System.exit( -1);                                                                
       } // End try/catch.   
   } // End writeMonitors.


   public void readMonitors( String filename) { 

   int index; 
   int numberOfMonitors; 
   
   String          className;
   Class           aclass;
   Object          anObject;
      
   DataInputStream theStream;

       try { 
          theStream = new DataInputStream( 
                              new FileInputStream( filename));
          numberOfMonitors = theStream.readInt();
          theMonitors = new WarningCounter[ numberOfMonitors];                    
          for ( index =0; index < theMonitors.length; index++) {
             className = theStream.readUTF();    
             aclass    = Class.forName( className);
             anObject  = aclass.newInstance();
             theMonitors[ index]  = (WarningCounter) anObject;
          
             theMonitors[ index].read( theStream);           
          } // End for.  
          theStream.close();
       } catch ( Exception exception) { 
          System.out.println( "Exception thrown on writing ... abending");
          System.exit( -1);                                                                
       } // End try/catch.   
   } // End writeMonitors.


   public String toString(){ 

   StringBuffer theString = new StringBuffer();
   int          index;
   char         theRoom = 'A';
   
      for ( index =0; index < theMonitors.length; index++) {  
         theString.append( "Room " + theRoom + "   Now in room : " + 
                           theMonitors[ index].toString() + "\n");
         theRoom++;                           
      } // End for.
      return theString.toString(); 
   } // End toString;

} // End class HeterogeneousMonitors.