src/org/nutz/dao/util/DaoUp.java
public void setDao(Dao dao) {
        if (this.dao != null)
            log.infof("override old Dao=%s by new Dao=%s", this.dao, dao);
        this.dao = dao;
    }
public void setDao(Dao dao) {
        if (this.dao != null)
            log.infof("override old Dao=%s by new Dao=%s", this.dao, dao);
        this.dao = dao;
    }
主动设置Dao实例
@param dao Dao实例