objectvartest.java

编程之道--java程序设计入门源代码

/**
 *　通过这个程序，测试对象类型的动态绑定
 */
public class ObjectVarTest
{
	public static void main(String[] args)
	{
		B b = new B();
		C.method3(b);
	}
}

class A
{
	public void method1()
	{
		System.out.println("this is class A method1");
	}
}
	
class B extends A
{
	public void method1()
	{
		System.out.println("this is class B method1");
	}

	public void method2()
	{
		System.out.println("this is class B method2");
	}
}

class C
{
	public static void method3(A a)
	{
		a.method1();
	}
}