java.lang.ClassCastException 强制类型转换异常
主要原因 : 当父类强制转换成子类时候出现的异常 ,除非是子类转换成父类,父类再转换给子类
public class Test { public static void main(String[] args) { Parent parent = new Child(); Child child = (Child) parent; child.getAge(); child.getName(); } } class Parent{ public void getName(){ System.out.println("hello world"); } } class Child extends Parent{ public void getAge(){ System.out.println("25"); } }
如果把代码稍微修改下,就会报ClassCastException
public class Test { public static void main(String[] args) { Parent parent = new Parent(); Child child = (Child) parent; child.getAge(); child.getName(); } } class Parent{ public void getName(){ System.out.println("hello world"); } } class Child extends Parent{ public void getAge(){ System.out.println("25"); } }