manipulation.java

来自「thinking in java 书中源码 第四版」· Java 代码 · 共 19 行

//: generics/Manipulation.java
// {CompileTimeError} (Won't compile)

class Manipulator<T> {
  private T obj;
  public Manipulator(T x) { obj = x; }
  // Error: cannot find symbol: method f():
  public void manipulate() { obj.f(); }
}

public class Manipulation {
  public static void main(String[] args) {
    HasF hf = new HasF();
    Manipulator<HasF> manipulator =
      new Manipulator<HasF>(hf);
    manipulator.manipulate();
  }
} ///:~