Quick Start Guide for Java Beginners
Concise and easy-to-understand Java installation tutorial, easy to get started in the world of programming, specific code examples are needed
With the development of computer technology, programming has become indispensable in modern society missing part. As a commonly used programming language, Java is widely used in various fields, such as mobile application development, Web development, big data processing, etc. In order to perform Java programming smoothly, we first need to install the Java development environment (Java Development Kit, JDK for short). This article will provide readers with a concise and easy-to-understand Java installation tutorial, with specific code examples, allowing readers to easily enter the world of programming.
1. Download JDK
First, open Oracle’s official website (https://www.oracle.com/java/technologies/javase-jdk11-downloads.html) and go to the JDK download page Find the JDK version for your operating system. Select the appropriate download link based on your operating system. Generally speaking, Windows users can download the installer in exe format, while Mac users can download the installer in dmg format.
2. Install JDK
- Windows users
After downloading, double-click the downloaded exe file to run the installation program. Follow the instructions step by step to install. Generally speaking, the default configuration provided by the installer is sufficient. Finally, click the "Install" button to complete the installation process.
- Mac users
After the download is completed, double-click the downloaded dmg file and an installation window will pop up. Drag the JDK icon to the application folder, and then double-click the JDK icon in the application folder to enter the installation process. Follow the instructions step by step to install and use the default configuration provided by the installer. Finally, click the "Install" button to complete the installation process.
3. Configure environment variables
- Windows users
Open the "Control Panel", click "System and Security", select "System" and enter System panel. Click "Advanced System Settings" on the left, and in the pop-up "System Properties" window, click the "Environment Variables" button. In the "System Variables" section, find the variable named "Path" and add the JDK installation path after it, such as: C:Program FilesJavajdk-11.0.7 in. Click the "OK" button to save changes.
- Mac users
Open the Terminal application and enter the following command:
sudo nano /etc/paths
After entering the administrator password, a text will open editor. At the very bottom of the file, add the JDK installation path, such as: /Library/Java/JavaVirtualMachines/jdk-11.0.7.jdk/Contents/Home/bin. Press Ctrl X, then Y, and finally Enter to save changes.
4. Verify the installation
After the installation is completed, we need to verify whether the JDK is successfully installed. Open the command line interface (Command Prompt on Windows, Terminal on Mac) and enter the following command:
java -version
If you see the JDK version number and other details, congratulations, you have installed the JDK Already successful!
Code example:
The following is a simple Java code example to print the sentence "Hello, World!".
public class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World!"); } }
Create a file with the suffix .java on your computer, copy the above code into the file, and then save it. Use the command line tool to enter the directory where the file is saved, and then enter the following command to compile:
javac HelloWorld.java
After successful compilation, a file with the suffix .class will be generated in the same directory. Finally, enter the following command to run the compiled code:
java HelloWorld
The running result will be output in the command line interface: "Hello, World!". This means you have successfully run a piece of Java code.
Summary:
Through this article’s concise and easy-to-understand Java installation tutorial, we can easily get started in the world of programming. First, you need to download the JDK version for your operating system and follow the installer's instructions to install it. Then, depending on the operating system, corresponding environment variable configuration is required. Finally, we verified the installation was successful with a simple Java code example. I hope this article will be helpful to you and enable you to program in Java smoothly.
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