Detailed interpretation of Java installation tutorial to make you a programming master

Detailed interpretation of the Java installation tutorial will help you become a programming master. Specific code examples are needed

Introduction:
Java is a cross-platform, object-oriented programming Language that is versatile and can be used to develop a variety of applications. In order to be able to program Java smoothly, you first need to install the Java development environment (JDK) correctly. This article will explain the Java installation tutorial in detail and provide specific code examples to help beginners quickly master the installation steps and precautions.

1. Download the JDK installation package
First, download the JDK installation suitable for your operating system on the official website https://www.oracle.com/java/technologies/javase-jdk11-downloads.html Bag. As shown in Figure 1, select the JDK version corresponding to the operating system version to download.

Figure 1: Screenshot of Java official website download page

2. Install JDK
After downloading, double-click to run the downloaded JDK installation package and follow the prompts to complete the installation. During the installation process, you need to pay attention to the following points:
1. Select the installation path: It is recommended to choose the default installation path to facilitate subsequent use.
2. Make sure to check the "Set JAVA_HOME" option: This option will automatically configure the JAVA_HOME environment variable during the installation process to facilitate subsequent Java development.

3. Configure environment variables
After the installation is completed, you need to manually configure the JAVA_HOME and Path environment variables. The following are the specific steps:
1. Open the "System Properties" window: Right-click the "Computer" or "My Computer" icon, select "Properties" to open the system properties window.
2. Edit environment variables: Select "Advanced System Settings" and click the "Environment Variables" button in the pop-up window.
3. Configure JAVA_HOME: Click the "New" button in "System Variables". Fill in "JAVA_HOME" for the variable name, and fill in the JDK installation path for the variable value (for example: "C:Program FilesJavajdk-11.0.9").
4. Configure the Path variable: Find the Path variable in "System Variables", click the "Edit" button, and add the JDK installation path to the value of the Path variable (such as: ";%JAVA_HOME% in;") .
5. Save configuration: Click the "OK" button in sequence to save the configuration and close the window.

4. Verify the installation results
After the configuration is completed, you need to verify whether Java is installed successfully. Open the command line window (for Windows systems, hold down the Win key R, enter "cmd" and press the Enter key) and enter the "java -version" command. If the Java version number information is displayed, the installation is successful. as shown in picture 2.

Figure 2: Java version number information displayed in the command line window

Code example 1: Hello World program
In order to further verify the Java installation results, we can write a simple Hello World program . The following is the sample code:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

We save the above code as HelloWorld.java, and use the following command in the command line window to compile and run:

javac HelloWorld.java
java HelloWorld

If the command line outputs " Hello, World!", it means that Java is installed successfully and compilation runs normally.

Code example 2: summation program
In order to further become familiar with Java's syntax, we can write a summation program. The following is the sample code:

import java.util.Scanner;

public class Sum {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入两个整数：");
        int a = scanner.nextInt();
        int b = scanner.nextInt();
        int sum = a + b;
        System.out.println("它们的和是：" + sum);
    }
}

We save the above code as Sum.java, and use the following command in the command line window to compile and run:

javac Sum.java
java Sum

Enter two integers as prompted, The program will calculate their sum and output the result.

Summary:
This article explains the Java installation tutorial in detail and provides specific code examples. By correctly installing the Java development environment, we can smoothly perform Java programming and write various feature-rich applications. I hope this article can help beginners and help everyone become a programming master.

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