多态的实现机制

while (clazz != NULL) {
        Method* methods;
        size_t methodCount;
        size_t i;

        if (findVirtual) {
            methods = clazz->virtualMethods;
            methodCount = clazz->virtualMethodCount;
        } else {
            methods = clazz->directMethods;
            methodCount = clazz->directMethodCount;
        }
       
        for (i = 0; i < methodCount; i++) {
            Method* method = &methods[i];
            if (compareMethodHelper(method, name, returnType, argCount,
                            argTypes) == 0) {
                return method;
            }
        }

        if (! isHier) {
            break;
        }

        clazz = clazz->super;
    }

    return NULL;