dispath.java

来自「JAVA程序设计课程中各章节的程序实例。」· Java 代码 · 共 44 行

//Dynamic method dispath runtime polymorphism
class A
{
	void callme()
	{
		System.out.println("Call me in A method");
	}
}

class B extends A
{
	void callme()
	{
		System.out.println("Call me in B method");
	}
}

class C extends A
{
	void callme()
	{
		System.out.println("Call me in C method");
	}
}

class Dispath
{
	public static void main(String args[])
	{
		A a = new A();
		B b = new B();
		C c = new C();

		A r;//pay attention here!
		r = a;
		r.callme();

		r = b;
		r.callme();

		r = c;
		r.callme();
	}
}