A private variable or method may be used only by an instance of the class. : private « Modifiers « SCJP






class Complex {
   private double real,  imaginary;

 public Complex(double r, double i) {
   real = r; imaginary = i;
 }
 public Complex add(Complex c) {
   return new Complex(real + c.real,
   imaginary + c.imaginary);
 }
}

public class MainClass{
   public static void main(String[] argv) {
     Complex c1 = new Complex(1, 2);
     Complex c2 = new Complex(3, 4);
     Complex c3 = c1.add(c2);
     //double d = c3.real; // Illegal!
   }
 }








3.2.private
3.2.1.private members can be accessed only by code in the same class.
3.2.2.A private variable or method may be used only by an instance of the class.
3.2.3.An instance of a subclass is denied access for private features