Java简单问题 请大家解答

Question

class StaticDemo {
  static int x;// 1)
  int y;

  public static int getX() {// 2}
    return x;
  }

  public static void setX(int newX) {
    x = newX;
  }

  public int getY() {
    return y;
  }

  public void setY(int newY) {
    y = newY;
  }

}

public class Main {
  public static void main(String[] args) {
    System.out.println("静态变量x=" + StaticDemo.getX());
    System.out.println("实例变量y=" + StaticDemo.getY());
    StaticDemo a = new StaticDemo();
    StaticDemo b = new StaticDemo();
    a.setX(1);
    a.setY(2);
    b.setX(3);
    b.setY(4);
    System.out.println("静态变量a.x=" + a.getX());
    System.out.println("实例变量a.y=" + a.getY());
    System.out.println("静态变量b.x=" + b.getX());
    System.out.println("实例变量b.y=" + b.getY());
  }
}

请问问题在哪里呢

Answer 1

public static void setX(int newX) {
   this.x = newX;
  }