<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[C_Wangjq的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/C_Wangjq</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; C_Wangjq]]></copyright><item><title><![CDATA[微信机器人实现打卡提醒+每日一句]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/108698245</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/108698245</guid><author>C_Wangjq</author><pubDate>Sun, 20 Sep 2020 20:48:01 +0800</pubDate><description><![CDATA[shell 脚本


#打卡提醒 @all
curl --request POST 'https://qyapi.weixin.qq.com/cgi-bin/webhook/send?key=key' --header 'Content-Type: application/json' --data '{"msgtype":"text","text":{"content": "【打卡提醒
】","mentioned_list":["@all"]}}'
#每日一句 图文消息
response=`curl ht.]]></description><category></category></item><item><title><![CDATA[redis学习笔记-2]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/106226392</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/106226392</guid><author>C_Wangjq</author><pubDate>Wed, 20 May 2020 00:44:18 +0800</pubDate><description><![CDATA[第2章 简单动态字符串


redis未之间使用c语言中的字符串，而是自构建的一种简单动态字符串(SDS)


redis库中，包含字符串值得键值对在底层都是由sds实现的


示例





sds与c字符串的区别

len属性的存在使得strlen() 复杂度O(1)
杜绝缓存区溢出:api会自动扩展空间至执行所需的大小
减少修改字符串时带来的内存重分配次数，内存重分配通常是一个比较耗时的操作,free空间解除了字符串长度和底层数组长度之间的关联

通过未使用空间sds实现了空间预分配和惰性空间释放两种]]></description><category></category></item><item><title><![CDATA[Redis学习笔记 - 链表]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/106226026</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/106226026</guid><author>C_Wangjq</author><pubDate>Tue, 19 May 2020 23:57:01 +0800</pubDate><description><![CDATA[文章目录redis命令手册第三章 链表链表和链表节点的实现重点回顾
redis命令手册
第三章 链表

拥有高效的节点重排能力
顺序性的节点访问方式
灵活调整链表长度
redis构建了自己的链表实现
redis中列表键的底层实现之一就是链表
发布与订阅、慢查询、监视器等功能也用到了链表
redis服务器本身还使用链表来保存多个客户端的状态信息
已经使用链表来构建客户端输出缓冲区

链表和链表节点的实现


adlist.h/listNode 结构表示
typedef stuct listNode{
    ]]></description><category></category></item><item><title><![CDATA[java.io.FileWriter使用]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105826864</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105826864</guid><author>C_Wangjq</author><pubDate>Tue, 28 Apr 2020 22:49:22 +0800</pubDate><description><![CDATA[简介

java.io.FileWriter

FilterWriter

FileWriter是一个专门用于编写字符文件的OutputStreamWriter。它不公开任何新操作，而是使用继承自OutputStreamWriter和Writer类的操作。
在Java 11之前，FileWriter一直使用默认的字符编码和默认的字节缓冲区大小。但是，Java 11引入了四个接受Charset的新构...]]></description><category></category></item><item><title><![CDATA[java spi学习；示例；]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105804160</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105804160</guid><author>C_Wangjq</author><pubDate>Tue, 28 Apr 2020 00:50:19 +0800</pubDate><description><![CDATA[概述
Java 6引入了一个用于发现和加载与给定接口匹配的实现的特性:服务提供者接口(Service Provider interface, SPI)。
在本文，我们将介绍Java SPI的组件，并展示如何将其应用到实际的用例中。
Java SPI的术语和定义
Java SPI定义了四个主要组件


service
一组编程接口和类，它们提供对某些特定应用程序功能或特性的访问。


service...]]></description><category></category></item><item><title><![CDATA[Class CountDownLatch]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105803294</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105803294</guid><author>C_Wangjq</author><pubDate>Tue, 28 Apr 2020 00:05:44 +0800</pubDate><description><![CDATA[Class CountDownLatch

描述


它允许一个或多个线程等待，直到在其他线程中执行的一组操作完成为止。


使用给定的count初始化CountDownLatch。


await方法阻塞，直到调用countDown()方法使当前计数为零


之后释放所有等待线程，并立即返回任何后续的await调用


这是一种一次性现象——计数无法重置。如果需要重新设置计数的版本，请考虑使用C...]]></description><category></category></item><item><title><![CDATA[SQLException;You must configure either the server to use a more specifc time zonevalue]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105780147</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105780147</guid><author>C_Wangjq</author><pubDate>Sun, 26 Apr 2020 23:33:45 +0800</pubDate><description><![CDATA[问题
SQLException: The server time zone value ‘XXX’ is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration prope...]]></description><category></category></item><item><title><![CDATA[Feign 工作流程图解]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105649068</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105649068</guid><author>C_Wangjq</author><pubDate>Tue, 21 Apr 2020 01:32:51 +0800</pubDate><description><![CDATA[feign 工作流程图

feign 创建动态代理类

feign 请求流程


]]></description><category></category></item><item><title><![CDATA[java 循环时，多线程处理的对象被更新,问题排查]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105649031</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105649031</guid><author>C_Wangjq</author><pubDate>Tue, 21 Apr 2020 01:16:21 +0800</pubDate><description><![CDATA[循环时，多线程处理的对象被更新
需要注意每次的循环调用 new 一个对象
原因：不使用多线程是为本地过程调用不会在打印之前再操作对象
import lombok.Data;
import lombok.val;

import java.util.ArrayList;

public class Demo {
    public static void main(String[] args) {...]]></description><category></category></item><item><title><![CDATA[Mybatis 资料链接汇总]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105463717</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105463717</guid><author>C_Wangjq</author><pubDate>Sun, 12 Apr 2020 01:36:02 +0800</pubDate><description><![CDATA[Mybatis 资料导航栏
持续更新




分类




mybatis官方文档







mybatis








入门






xml配置






映射器mappers
属性properties
设置settings
类型别名typeAliases



类型处理器typeHandlers
对象工厂objectFactory
插件plugin-intercepror
环境配...]]></description><category></category></item><item><title><![CDATA[mybatis 入门篇]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105463360</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105463360</guid><author>C_Wangjq</author><pubDate>Sun, 12 Apr 2020 00:32:40 +0800</pubDate><description><![CDATA[参考：mybatis.org文档

入门

入门篇主要讲了以下内容，详细请转至官网查看
文章目录引入依赖从 XML 中构建 SqlSessionFactory不使用 XML 构建 SqlSessionFactory从 SqlSessionFactory 中获取 SqlSession探究已映射的 SQL 语句作用域（Scope）和生命周期SqlSessionFactoryBuilderSqlSess...]]></description><category></category></item><item><title><![CDATA[mybatis-BindingException: Parameter 'userId' not found. Available parameters]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105458420</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105458420</guid><author>C_Wangjq</author><pubDate>Sat, 11 Apr 2020 19:54:58 +0800</pubDate><description><![CDATA[可能原因


多参数查询时，参数绑定失败，缺少@param 参数


关键报错：

BindingException
Parameter ‘userId’ not found. Available parameters are [arg1, arg0, param1, param2]

    /**
     * 多参数查询
     * @param userId 用户id
     * @p...]]></description><category></category></item><item><title><![CDATA[mybatis insert用法;属性介绍,简单使用]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105457631</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105457631</guid><author>C_Wangjq</author><pubDate>Sat, 11 Apr 2020 18:54:52 +0800</pubDate><description><![CDATA[元素，标签属性介绍，用法
    &lt;!--insert标签包含以下属性
     id:命名空间中的唯一标志符，可用来代表这条语句
     parameterType:将传入的语句参数的完全限定类名或别名，这个属性是可选的，mybatis可用推断出传入语句的具体参数，因此不建议配置改属性
     flushCache:default true,任何时候只要语句被调用，都会清空一级缓存和二...]]></description><category></category></item><item><title><![CDATA[mybatis配置日志输出；mybatis-config]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105456113</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105456113</guid><author>C_Wangjq</author><pubDate>Sat, 11 Apr 2020 17:30:25 +0800</pubDate><description><![CDATA[mybatis-config.xml配置文件中
&lt;configuration&gt;
&lt;settings&gt;标签下增加配置
 &lt;settings&gt;
        &lt;setting name="logImpl" value="STDOUT_LOGGING"/&gt;
 &lt;/settings&gt;

pom ：jar依赖配置
		&lt;!--log--&g...]]></description><category></category></item><item><title><![CDATA[InstantiationAwareBeanPostProcessor；bean实例化后增强；字段注入]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105417732</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105417732</guid><author>C_Wangjq</author><pubDate>Thu, 09 Apr 2020 19:10:00 +0800</pubDate><description><![CDATA[文章目录Interface InstantiationAwareBeanPostProcessorpostProcessAfterInstantiation(Object bean, String beanName)postProcessBeforeInstantiation(Class&lt;?&gt; beanClass, String beanName)postProcessProperti...]]></description><category></category></item><item><title><![CDATA[mybatis-PersistenceException-MySQLNonTransientConnectionException: Could not connection server]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105401032</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105401032</guid><author>C_Wangjq</author><pubDate>Thu, 09 Apr 2020 00:15:20 +0800</pubDate><description><![CDATA[mybatis-PersistenceException-MySQLNonTransientConnectionException: Could not create connection to database server
可能原因


jar包版本问题


mysql-connector-java版本不匹配


mysql -uroot -p 查看版本号
Welcome to the MyS...]]></description><category></category></item><item><title><![CDATA[mybatis-PersistenceException-IncompleteElementException: Could not find result map]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105400752</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105400752</guid><author>C_Wangjq</author><pubDate>Wed, 08 Apr 2020 23:59:47 +0800</pubDate><description><![CDATA[原因


误将mapper.xml中resultType写成了resultMap


关键报错： Could not find result map
    &lt;select id="selectAll" resultType="com.dayu.mybatis.simple.model.Country"&gt;
        SELECT id,countryname,countrycod...]]></description><category></category></item><item><title><![CDATA[EnvironmentAware;获取运行环境中变量;使用:加载配置文件]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105377193</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105377193</guid><author>C_Wangjq</author><pubDate>Tue, 07 Apr 2020 23:48:51 +0800</pubDate><description><![CDATA[文章目录Interface EnvironmentAwaresetEnvironment(Environment environment)使用场景
Interface EnvironmentAware


org.springframework.context.EnvironmentAware

setEnvironment(Environment environment)



任何实现这个接口...]]></description><category></category></item><item><title><![CDATA[MethodInterceptor;方法调用拦截器;使用:打印操作日志,阿里sentinal接入用于服务降级]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105376613</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105376613</guid><author>C_Wangjq</author><pubDate>Tue, 07 Apr 2020 23:14:30 +0800</pubDate><description><![CDATA[文章目录Interface MethodInterceptorinvoke(MethodInvocation invocation)使用场景
Interface MethodInterceptor


org.aopalliance.intercept.MethodInterceptor

invoke(MethodInvocation invocation)



这是一个函数接口，因此可以用作...]]></description><category></category></item><item><title><![CDATA[ApplicationListener;监听事件;使用:服务启动后上报数据]]></title><link>https://blog.youkuaiyun.com/C_Wangjq/article/details/105371975</link><guid>https://blog.youkuaiyun.com/C_Wangjq/article/details/105371975</guid><author>C_Wangjq</author><pubDate>Tue, 07 Apr 2020 19:42:18 +0800</pubDate><description><![CDATA[Interface ApplicationListener


org.springframework.context.ApplicationListener

onApplicationEvent(E event)



E:要侦听的特定ApplicationEvent子类


这是一个函数接口，因此可以用作lambda表达式或方法引用 赋值目标


由应用程序事件侦听器实现的接口。基于标准ja...]]></description><category></category></item></channel></rss>