这是@Omar Kooheji建议的as的实现:
public static <T> T as(Class<T> clazz, Object o){ if(clazz.isInstance(o)){ return clazz.cast(o); } return null;}as(A.class, new Object()) --> nullas(B.class, new B()) --> B
这是@Omar Kooheji建议的as的实现:
public static <T> T as(Class<T> clazz, Object o){ if(clazz.isInstance(o)){ return clazz.cast(o); } return null;}as(A.class, new Object()) --> nullas(B.class, new B()) --> B