leaf.java

Object-Based Programming 语言基础 java 教程

public class Leaf {
  private int i = 0;
  Leaf increment() {
    i++;
    return this;
  }
  void print() {
    System.out.println("i = " + i);
  }
  public static void main(String[] args) {
    Leaf x = new Leaf();
   x.increment().increment().increment().print();
  }
}