src/org/nutz/service/EntityService.java
@SuppressWarnings("unchecked")
    public <C extends T> void setEntityType(Class<C> classOfT) {
        mirror = (Mirror<T>) Mirror.me(classOfT);
    }
@SuppressWarnings("unchecked")
    public <C extends T> void setEntityType(Class<C> classOfT) {
        mirror = (Mirror<T>) Mirror.me(classOfT);
    }
设置新的实体类型, 极少调用

@param classOfT