how to check which jvm version is running actively

Daniel Parker

2 min read

·

05-02-2025

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Knowing your Java Virtual Machine (JVM) version is crucial for troubleshooting, ensuring compatibility, and optimizing your Java applications. This article will guide you through several methods to quickly and easily determine which JVM version is currently running. Whether you're a seasoned Java developer or just starting out, understanding this is a fundamental skill.

Methods to Identify Your Active JVM Version

There are several ways to check your active JVM version, depending on your operating system and environment. Here are the most common and reliable methods:

1. Using the java -version command (Most Common Method)

This is the simplest and most widely used method. Open your terminal or command prompt and type:

java -version

Press Enter. The output will clearly display the JVM version, vendor, and other relevant information, such as:

openjdk version "17.0.6" 2023-04-18 LTS
OpenJDK Runtime Environment (build 17.0.6+10-LTS-272)
OpenJDK 64-Bit Server VM (build 17.0.6+10-LTS-272, mixed mode, sharing)

This command works on Windows, macOS, and Linux. If you encounter an error like "command not found", ensure that Java is correctly installed and added to your system's PATH environment variable.

2. Using the System.getProperty("java.version") method (Within a Java Program)

If you need to determine the JVM version programmatically within a Java application, you can use this method:

public class JVMVersion {
    public static void main(String[] args) {
        String javaVersion = System.getProperty("java.version");
        System.out.println("Java Version: " + javaVersion);
    }
}

Compile and run this Java code. The output will print the JVM version currently running the program. This is useful for applications that need to adapt their behavior based on the JVM version.

3. Checking the Java Control Panel (Windows)

On Windows systems, you can also find the JVM version through the Java Control Panel:

1. Search for "Java" in the Windows search bar.
2. Open the "Java Control Panel".
3. Go to the "Java" tab.
4. Click on "View...". This will display a list of Java installations on your system. The currently active version will likely be indicated.

This method shows you all installed versions of Java on your system which can be helpful if you have multiple versions installed. However, the command line method is generally faster and more reliable.

4. Examining the java executable properties (Linux/macOS)

On Linux and macOS systems, you can inspect the properties of the java executable. This might provide more information, especially if you have multiple Java installations:

file $(which java)

This command will output information about the java executable, including the version information embedded within the file.

Troubleshooting Common Issues

• java command not found: This indicates that Java is not installed or not correctly configured in your system's PATH. You'll need to install Java and update your system's PATH environment variable. Refer to your operating system's documentation for instructions.
• Multiple Java versions: If you have multiple Java versions installed, ensure the correct one is in your PATH. Adjust your PATH environment variable to prioritize the desired JVM version.

Conclusion

Checking your active JVM version is a straightforward process with several reliable methods. The java -version command is the quickest and most widely applicable method for most users. Remember to choose the method that best suits your needs and environment. Understanding your JVM version is a fundamental step in Java development and troubleshooting. Knowing this information allows for better compatibility and performance optimization.