Mam problem z ustaleniem, jak porównać wybrane radio pomiędzy AM FM I XM, aby móc określić, które z nich jest aktualnie włączone, a następnie zwrócić stację danego radia. Wiem, że potrzebuję metody równości, po prostu nie jestem pewien, w jaki sposób ją wykorzystać, aby uzyskać wynik, którego szukam.

public class AutoRadioSystem
    {
      private Radio selectedRadio;
      private AMRadio radioAM;
      private FMRadio radioFM; 
      private XMRadio radioXM;

      //I'm not sure if this is the correct way to do this so that selectedRadio equals the object of radioAM
      public AutoRadioSystem()
      {
        selectedRadio = radioAM;
      }
     //trying to figure out how to compare if selectedRadio is one of these. 
      public double getCurrentStation()
      {
        if (selectedRadio == radioAM)
        {
          return radioAM.getCurrentStaion();
        }
        else if (selectedRadio == radioFM)
        {
          return radioFM.getCurrentStaion();
        }
        return 0.0;
      }
      // its supposed to switch the radio from AM to FM when this method is called 
      public void selectRadio()
      {
        if (selectedRadio.equals(radioAM))
          selectedRadio = radioFM;
      }
      public boolean equals (Object o)    
     {        
       if (o == null)           
         return false;        
       if (! (o instanceof AutoRadioSystem))           
         return false;       
       AutoRadioSystem other = (AutoRadioSystem) o;       
       return this.selectedRadio == other.selectedRadio;    
     }
      public static void main (String [] args) { 
        AutoRadioSystem c = new AutoRadioSystem();
        c.selectRadio();
        double b = c.getCurrentStation();
        System.out.println(b);
      }
    }


public abstract class Radio 
{
 double currentStation;

 RadioSelectionBar radioSelectionBar;
 public Radio()
 {
   this.currentStation = getMin_Station();
 }
 public abstract double getMax_Station();
 public abstract double getMin_Station();
 public abstract double getIncrement();
 public void up()
 {

 }
 public void down()
 {

 }
 public double getCurrentStaion()
 {
   return this.currentStation;
 }
 public void setCurrentStation(double freq)
 {
   this.currentStation = freq;
 }
 public void setStation(int buttonNumber, double station)
 {
 }
 public double getStation(int buttonNumber)
 {
   return 0.0;
 }
 public String toString()
 {
   String message = ("" + currentStation);
   return message;
 } 

 public boolean equals (Object o)    
 {        
   if (o == null)           
     return false;        
   if (! (o instanceof Radio))           
     return false;       
   Radio other = (Radio) o;       
   return this.currentStation == other.currentStation;    
 }

 public static void main(String[] args)
 {
   Radio amRadio = new AMRadio();

   System.out.println(amRadio);

   Radio fmRadio = new FMRadio();

   System.out.println(fmRadio);

   Radio xmRadio = new XMRadio();

   System.out.println(xmRadio);

 }  
}



public class FMRadio extends Radio
{
  private static final double Max_Station = 108.0;
  private static final double Min_Station = 88.0;
  private static final double Increment = .01;
  public FMRadio()
  {
    currentStation = Min_Station;
  }
  public  double getMax_Station()
  {
    return this.Max_Station;
  }
  public  double getMin_Station()
  {
    return this.Min_Station;
  }
  public  double getIncrement()
  {
    return this.Increment;
  }
  public String toString()
  {
    String message = ("FM " + this.currentStation);
    return message;
  } 
}