应开发内网命名服务的需求，需要调研Java是如何使用DNS的。以下文字是调研的一些结果，主要关注本地缓存、过期时间、多条A记录的选择策略以及如何自定义解析规则等方面。调研对象为JDK8。
标签： Java
As we all know in database query is about computation. Computation requires data deserialized as objects in memory. So how object layout in memory and how many memory it cost is very important especially for waste memory operators like group-by, join, count-distinct etc.
Java7 HashMap原理分析，以及由此引发的思考。