Table of contents
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First look at the article directory to get a general understanding of the structure of the knowledge points. You can directly click on the article directory to jump to the specified location of the article.
Chapter 1, JVM, JRE, JDK Introduction
(1) JVM (JVM Java Virtual Machine): The core mechanism, the Java virtual machine
JVM is a virtual computer with an instruction set and uses different storage areas. Responsible for executing instructions, managing data, memory, and registers. The Java virtual machine mechanism shields the differences of the underlying operating platforms and realizes "compile once, run across platforms".
(2) JRE (Java Runtime Environment)
includes the Java virtual machine and the core class libraries required by Java programs. If you want to run a developed Java program, you only need to install JRE in the computer.
(3) JDK (Java Development Kit Java Development Kit)
which contains java development tools, including JRE. So after installing the JDK, there is no need to install the JRE separately. Among them, the development tools: compilation tool (javac.exe), packaging tool (jar.exe), etc.
Chapter 2, Download and Install JDK
2.1) Baidu network disk direct download without installation
①My Baidu network disk downloads for free: Baidu network disk extraction code bybp
②After downloading
, you can use it directly without installation
2.2) Download and install JDK from the official website (fee required)
①Download from oracle official website (fees are not recommended): Official website download address
②Double-click the installation file after downloading, just go to the next step without thinking
③Change the installation directory ③Continue
to the next step until installation
Chapter 3, Environment variable configuration
3.1) Windows environment variable configuration
①Win+E to open the manager –> This computer –> Properties
②Choose advanced system settings ③Choose
environment variables ④Create
new system variables ⑤Enter the variable name and the file path
downloaded and installed before, click OK %JAVA_HOME%\bin
3.2) Verify whether the environment variable is configured successfully
After confirmation, win+r, enter cmd to open the command window, enter javac to run, and the following interface will appear after success
