title: How to Count Number of Instances of a Class
body: <p>Can anyone tell me how to count the number of instances of a class?</p>
  
  <p>Here's my code </p>
  
  <pre><code>public class Bicycle {
  
      //instance variables
      public int gear, speed, seatHeight;
      public String color;
  
      //constructor
      public Bicycle(int gear, int speed, int seatHeight, String color) {
          gear = 0;
          speed = 0;
          seatHeight = 0;
          color ="Unknown";      
      }
  
      //getters and setters
      public int getGear() {
          return gear;
      }
      public void setGear(int Gear) {
          this.gear = Gear;
      }
  
      public int getSpeed() {
          return speed;
      }
      public void setSpeed(int Speed){
          this.speed = Speed;
      }
  
      public int getSeatHeight() {
          return seatHeight;
      }
      public void setSeatHeight(int SeatHeight) {
          this.seatHeight = SeatHeight;
      }
  
      public String getColor() {
          return color;
      }
      public void setColor(String Color) {
          this.color = Color;
      }
  
   }//end class
  
  
  
  public class Variable extends Bicycle {
  
      public Variable(int gear, int speed, int seatHeight, String color) {
          super(gear, speed, seatHeight, color);
  
      }
  
  }//end class
  
  
  public class Tester {
  
      public static void main(String args[]){
  
  
         Bicycle bicycle1 = new Bicycle(0, 0, 0, null);
         bicycle1.setColor("red");
         System.out.println("Color: "+bicycle1.getColor());
         bicycle1.setSeatHeight(4);
         System.out.println("Seat Height: "+bicycle1.getSeatHeight());
         bicycle1.setSpeed(10);
         System.out.println("Speed: "+bicycle1.getSpeed());
         bicycle1.setGear(6);
         System.out.println("Gear: "+bicycle1.getGear());
  
         System.out.println("");//space
  
         Bicycle bicycle2 = new Bicycle(0, 0, 0, null);
         bicycle2.setColor("black");
         System.out.println("Color: "+bicycle2.getColor());
         bicycle2.setSeatHeight(6);
         System.out.println("Seat Height: "+bicycle2.getSeatHeight());
         bicycle2.setSpeed(12);
         System.out.println("Speed: "+bicycle2.getSpeed());
         bicycle2.setGear(6);
         System.out.println("Gear: "+bicycle2.getGear());
  
         System.out.println("");//space
  
      }//end method
   }//end class
  </code></pre>
  
  <p>The class variable is to be used to keep count of the number of instances of the Bicycle class created and the tester class creates a number of instances of the Bicycle class and demonstrates the workings of the Bicycle class and the class variable. I've looked all over the internet and I can't seem to find anything, could someone show me how to do it please, thanks in advance :)</p>