Javase learning 01 – building an introductory environment

Time:2021-10-11

Xiaobai, a newcomer to the workplace, is ready to develop in the direction of big data. She learned the ES tutorial of crazy God at station B. because she likes his teaching, she is ready to learn java completely again and take notes while watching the teaching

Java learning complete route, it is strongly recommended to collect and forward

Markdown learning

title

Tertiary title

Four level title

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Hello,World!

Hello,World!

Hello,World!

Hello,World!

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Learning never ends >

Split line


< — >< *** >


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Hyperlinks

[Click to jump to my blog]((https://www.cnblogs.com/xsyw/)
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  1. A
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  • A
  • B
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form

name Gender birthday
Zhang San male 2020.01.01

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hello

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The origin of computer

Von Neumann — the father of modern computer

约翰·冯·诺依曼
John von Neumann (December 28, 1903-february 8, 1957), an American Hungarian mathematician, computer scientist and physicist, is one of the most important mathematicians in the 20th century. Von Neumann is a doctor of mathematics of Roland University. He is one of the scientific generalists in the fields of modern computer, game theory, nuclear weapons and biological and chemical weapons. He is called “the father of modern computer” and “the father of game theory” by later generations.

Von Neumann architecture

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Computer shortcut

  1. ctrl+Ccopyctrl+Vpaste

    ctrl+ASelect allctrl+Xshear

    ctrl+Zrevokectrl+Spreservation

  2. win+ROpen the command line window

    win+ETurn on my computer

    ctrl+shift+escOpen Task Manager

  3. Create virtual desktop
    win+ctrl+D

  4. Switching between virtual desktops
    win+crtl+ Or - >

    Close virtual desktop
    win+crtl+F4

  5. Minimize all windows at once
    win+M

  6. Quickly open an application in the application bar
    Win + Digital

  7. Application split screen
    win+Or win + - >

  8. Application switching
    crtl+alt+tabDisplays all applications currently in use
    win+tabShow task window
    alt+tabSwitch programs without display

  9. Program management and troubleshooting
    crtl+shift+escOpen Task Manager

  10. Open the document browser
    win+E

  11. Use a magnifying glass
    win++or-

  12. Capture screen
    win+prtScScreen capture

  13. Use operation center
    win+A

  14. Enter settings
    win+I

  15. Using the game bar
    win+G

  16. Lock the PC
    win+L

DOS command

win+REnter CMD to open the console, or press and hold in any foldershift+Right click to open the current command line window

Common DOS commands

#D: Drive letter switching
#Dir view all files in the current directory
#CD change directory
#CD.. return to parent directory
#CLS clean screen
#Exit exit terminal
#Ipconfig view the IP address of the computer
#Ping command
#MD create folder
#Rd remove folder
#CD > create file
#Del delete file

JDK

Select the official website to downloadjdk1.8Java SE Development Kit 8 – Downloads (oracle.com)

installjdk1.8reachDDisk, configuring environment variables:

  • JAVA_ HOME JDK installation directory D: \ jdk1.8.0_ one hundred and eleven
  • CLASSPATH .;%JAVA_HOME%\lib;%JAVA_HOME%\lib\tools.jar
  • Path to add two D: \ jdk1.8.0_ 111\bin D:\jdk1.8.0_ 111\jre\bin

Verification configuration instruction:javajavacjava -version
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Hello World

  1. Just create a new folder to store the code

  2. Create a new Java file

    • The file suffix is. Java
    • Hello.java
  3. Write code

    public class Hello{
    		public static void main(String[] args){
               System.out.print("Hello,World!");
           }
       }
  4. Compiling javac java files will generate a class file

  5. Run class file, Java class file

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IDEA

Use idea development tools to develop directlyOfficial websiteDownload the enterprise version (I use the plug-in for unlimited trial. The method comes from station B).

After installation, create a new project, select Java, select JDK1.8 installed above, enter the development interface, create a class class in the SRC folder of the project column on the left, and the. Java file appears. Use the shortcut PSVM and South in the. Java file, enter the text you want to output in println (), and click Run

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