How to check Java version in terminal?

How to Check Java Version in Terminal?

In this article, we will explore how to check the Java version in a terminal, a fundamental question for any Java developer or user. Before diving into the steps, let’s understand why checking the Java version is crucial.

Why Check Java Version?

Checking the Java version is essential for various reasons, including:

• Troubleshooting Java-related issues: When dealing with Java-related problems, it’s essential to know the version of Java installed on your system to identify potential issues and find suitable solutions.
• Compatibility issues: Different Java versions have varying levels of support for different features, libraries, and frameworks. Knowing the Java version helps you identify potential compatibility issues when working with different projects or libraries.
• Upgrading or Downgrading Java: When upgrading or downgrading Java, it’s crucial to know the current version to plan the transition smoothly.

How to Check Java Version in Terminal?

There are two primary ways to check the Java version in a terminal:

1. Using the java -version Command

Step 1: Open a Terminal

Open your terminal (or command prompt) on your operating system.

Step 2: Type the Command

Type the following command and press Enter:

java -version

Step 3: View the Output

You should see the Java version output, which may look similar to the following:

java version "1.8.0_275"

Java(TM) SE Runtime Environment (build 1.8.0_275-b15)

Java HotSpot(TM) 64-Bit Server VM (build 25.275-b15, mixed mode)

The output will display the Java version number, the Java SE Runtime Environment, and the Java HotSpot VM version.

2. Using the javac Command

Step 1: Open a Terminal

Open your terminal (or command prompt) on your operating system.

Step 2: Type the Command

Type the following command and press Enter:

javac -version

Step 3: View the Output

You should see the Java version output, which may look similar to the following:

javac 1.8.0

Note that both methods produce similar output, but javac provides more detailed information, including the compiler version.

Tips and Variations

• If you have multiple Java versions installed on your system, you can specify the version you want to check by prefixing the command with the version number, such as java -1.8 -version or javac -1.8 -version.
• On some systems, you may need to use the full path to the java or javac executable, such as /usr/bin/java -version or /usr/local/bin/javac -version.

Conclusion

Checking the Java version is a fundamental task for any Java user or developer. By using the java -version or javac -version commands, you can easily determine the version of Java installed on your system. Remember to take note of the version number, as it may be crucial for troubleshooting, compatibility, or upgrading/downgrading Java. Happy coding!