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Background: jstack is used to generate a thread snapshot of the current time of the JVM. It can locate problems such as thread deadlock, dead cycle, thread pause caused by too long external request time. Thread classification: gc thread Tomcat worker thread Tomcat Boss thread (IO thread) Dubbo Netty JIT thread [CompilerThread3] User d ...

1 create an empty project first (name yourself) 2 create two modules in the empty project created in step 1, and the creation method is as shown in the following figure. 1) create initiator module with maven project my initiator name is Mao spring boot starter pom.xml As shown below <?xml version="1.0" encoding="UTF-8"?> <projec ...

I. Introduction to Lombok Lombok It is a java development plug-in, which enables Java developers to eliminate tedious and tedious code in business engineering through some annotations defined by it, especially for simple java model objects (POJO s). After using Lombok plug-in in the development environment, Java developers can save a lot of ti ...

When using Mybatis, you may have a question: why can you only write Mapper interface to operate database? Its main idea is to use dynamic agent to generate implementation class, and then cooperate with SQL statement in xml Mapping file to access database. Let's take a look at the source code. binding module core class Mapper registry: the regi ...

I. about Feign Feign means "pretend, camouflage, transform" in English. It is a lightweight framework for http request calling. It can send http request in the way of interface annotation instead of http client calling by encapsulating http request message. Feign templates the request by processing comments. When it is actually calle ...

Using development tools: Spring Tool Suite 4 Create a Maven project Select File - > New - > others - > Maven - > Maven project Create a simple project(skip archetype selection) Use default Workspace location Add project(s) to working set Choose project type: usually choose to build Maven archetype QuickStart (non web proj ...

Create user sudo useradd --system --home /opt/tomcat --shell /sbin/nologin --comment "tomcat user" --user-group tomcat Deploying tomcat Unzip the installation package: tar -xvf apache-tomcat-9.0.21.tar.gz Mobile decompression package: sudo mv apache-tomcat-9.0.21 /opt/tomcat/apache-tomcat-9.0.21 To create a soft link: sudo ln -s /opt/tomcat/ ...

After the front and back ends are separated, it is essential to maintain the interface documents. An ideal state is that after the design is completed, the interface documents will be sent to the front-end and back-end, and each of them will develop according to the established rules. After the development is completed and connected, they can g ...

The default logging framework used by springboot is Logback. Simple log properties can be configured in application.properties, logback.xml format can be configured separately, and log4j can be used for management. The following describes the self-contained log configuration and how to use log4j as log ...

When installing through brew on mac system, the local default installation address is / usr / local / cell / Apache Flink / 1.5.1 1. Can I call graph algorithm in flink? It can be called in dataSet, and it needs to write its own method in dataStream. It can be implemented in scala by itself, just by r ...