car.java

thinking in Java书中 的源代码

//: c06:Car.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// Composition with public objects.

class Engine {
  public void start() {System.out.println("Engine.start()");}
  public void rev() {System.out.println("Engine.rev()");}
  public void stop() {System.out.println("Engine.stop()");}
}

class Wheel {
  public void inflate(int psi) {System.out.println("Wheel.inflate("+psi+")");}
}

class Window {
  public void rollup() {System.out.println("Window.rollup()");}
  public void rolldown() {System.out.println("Window.rolldown()");}
}

class Door {
  public Window window = new Window();
  public void open() {System.out.println("Door.open()");}
  public void close() {System.out.println("Door.close()");}
}

public class Car {
  public Engine engine = new Engine();
  public Wheel[] wheel = new Wheel[4];
  public Door left = new Door(),
       right = new Door(); // 2-door
  public Car() {
    for(int i = 0; i < 4; i++)
      wheel[i] = new Wheel();
  }
  public static void main(String[] args) {
    Car car = new Car();
    car.left.window.rollup();
    car.wheel[0].inflate(72);
  }
} ///:~