子类是永远继承父类的非私有化方法,当子类中重写父类方法时,调用的是子类的方法,没有重写时,调用的是父类中的方法 1 多态是只针对方法,而不是属性的,但是写法上,子类重写父类的属性,编译器是不会报错的 class Person{ String name = "person" ; public void shout(){ System.out.println(name); }} class Stu extends Person{ String name = "student&qu
USE [test] GO /****** Object: StoredProcedure [dbo].[p04_get_groupno_cleared] Script Date: 2019/7/8 15:03:02 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROC [dbo].[p04_get_groupno_cleared] AS --s4,对被包含过的组进行清理,只保留未被包含过的组 BEGIN IF O
Netty官网:https://netty.io/ Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. Java技术栈方向的朋友应该或多或少都听说过Netty是对Java中nio ( Non Blocking IO )的封装,让我们能快速开发出性能更
今天我司线上kafka消息代理出现错误日志,异常rebalance,而且平均间隔2到3分钟就会rebalance一次,分析日志发现比较严重.错误日志如下 08-09 11:01:11 131 pool-7-thread-3 ERROR [] - commit failed org.apache.kafka.clients.consumer.CommitFailedException: Commit cannot be completed since the group has already r