java类型转换，java类型,package cn.o

java类型转换，java类型,package cn.o

package cn.outofmemory.snippets.core;public class ClassCast {    public static void main(String[] argv) {        A aObject = new A();        B bObject = new B(1);        C cObject = new C(2, 3);        System.out.println("A = " + aObject);        System.out.println("B = " + bObject);        System.out.println("C = " + cObject);        A aCasted = cObject;        System.out.println("aCasted = " + aCasted);        C secondC = (C) aCasted;        System.out.println("secondC = " + secondC);    }}class A {}class B extends A {    int a;    B(int i) {        a = i;    }    public String toString() {        return "In a B object: " + a;    }}class C extends B {    int b;    C(int i, int j) {        super(i);  // does "one = i" for us.        b = j;    }    public String toString() {        return "In a C object: " + a + "," + b;    }}

输出：

A = methodoverloading.A@e9f784dB = In a B object: 1C = In a C object: 2,3aCasted = In a C object: 2,3secondC = In a C object: 2,3