Category:Java

  • First meet docker

    Time:2021-10-22

    Series articles: First meet docker Docker installation Run process and docker principle Docker common commands Summary of common docker commands Docker actual deployment visualization Docker image explanation Docker learning Docker overview Docker installation Docker command Mirror command Container command Operation command 。。。 Docker image! Container data volume! DockerFile Docker network principle Idea integration docker Docker […]

  • Summer self-study day 13 | database (VI) – multi table query

    Time:2021-10-22

    Series articles: Summer self-study day 09 | database (I) – SQL, DDL Summer self-study day 10 | database (II) – DML Summer self-study day 10 | database (III) – DQL Summer self-study day 11 | database (IV) – constraints Summer self-study day 12 | database (V) – multi table, database design Summer self-study day 13 […]

  • Transformation of message oriented middleware under distributed services

    Time:2021-10-22

    1、 Background introduction In the early stage of system development, it is easy for developers on different business lines to give priority to familiar ones in model selection due to the influence of technology stack and version time, such as Kafka, rocket, rabbit, etc. commonly used in MQ middleware, so it is easy to ignore […]

  • The same variable name in mybatis #foreach causes the value override problem to be solved

    Time:2021-10-22

    catalogue background Cause of problem (abbreviated version) Mybatis process source code analysis (long text warning, self access on demand) 1、 Get sqlsessionfactory 2、 Get sqlsession 3、 Execute SQL background Use mybatis to execute the following query: unit testing @Test public void test1() { String resource = “mybatis-config.xml”; InputStream inputStream = null; try { inputStream = […]

  • Summer self-study day 14 | database (VII) – affairs

    Time:2021-10-21

    Series articles: Summer self-study day 09 | database (I) – SQL, DDL Summer self-study day 10 | database (II) – DML Summer self-study day 10 | database (III) – DQL Summer self-study day 11 | database (IV) – constraints Summer self-study day 12 | database (V) – multi table, database design Summer self-study day 13 […]

  • Docker image optimization: from 1.16 GB to 22.4mb! How??

    Time:2021-10-21

    Source:http://blog.csdn.net/update7 Docker introduction Docker is a platform for software developers and system administrators to build, run and share applications using containers. A container is a process running in a stand-alone environment. It runs on its own file system, which is built using a docker image. The image contains everything needed to run the application (compiled […]

  • The mybatis query statement returns operations on objects and generic collections

    Time:2021-10-21

    Mybatis query statements return objects and generic collections Empmapper mapping interface: package cn.et.mybatis.lesson03; import java.util.List; import org.apache.ibatis.annotations.Result; import org.apache.ibatis.annotations.Results; import org.apache.ibatis.annotations.Select; public interface EmpMapper { /** *Query a single piece of data, *The column name of each column will match the corresponding attribute in the EMP entity class *When matching, both sides will be turned […]

  • Run process and docker principle

    Time:2021-10-20

    Series articles: First meet docker Docker installation Run process and docker principle Docker common commands Summary of common docker commands Docker actual deployment visualization Docker image explanation Operation process Underlying principle How does docker workDocker is a client server system. The daemon of docker runs on the host and is accessed from the client through […]

  • Thymeleaf

    Time:2021-10-20

    Spring integrates thymeleaf template engine, which is introduced in this article dialect Thymeleaf provides a flexible interface that allows users to customize their own dialects. Therefore, it is necessary to understand the standard dialect before customizing the dialect. Standard expression ${…}: variable expression Variable Variable expressions are usually ognl ${session.user.name} Thymeleaf <span th:text=”${book.author.name}”> Equivalent to […]

  • Learn the engine and host container of Tomcat (4)

    Time:2021-10-20

    In the previous article, we introduced the connector of Tomcat. The connector will listen to the specified port, convert the received message into HttpServletRequest and httpservletresponse, and submit it to a servlet container for processing. Tomcat’s servlet containers are divided into four types: engin container / host container / context container / wrapper container. These […]

  • Implementation of sharding JDBC custom composite partition (sub database and sub table)

    Time:2021-10-20

    catalogue Sharding JDBC data slicing strategy Slice key Partition algorithm Partition strategy SQL Hint Actual combat – custom composite fragmentation strategy Summary The sharding strategy in sharding JDBC has two dimensions: Database sharding strategy Table sharding strategy The data source fragmentation strategy represents the physical target data source to which the data is routed, and […]

  • El expression cross reference JSP built-in object table

    Time:2021-10-19

    El expression built-in (implicit) object pageContext Pagecontext object in JSP page can obtain other 8 objects pageScope Represents the data saved in the page field, the map object requestScope Represents the data saved in the request field, the map object sessionScope Represents the data saved in the session domain, the map object applicationScope Represents the […]