How to get the value of an environment variable in Java
What is an environment variable?
A dynamic value that the operating system and other applications may use to identify information particular to your machine is known as an environment variable.
Environment variables are in the form of key-value pairs, where the key indicates the variable’s name.
Problem overview
Given the environment variable name, fetch the value of the variable in Java.
Solution
We use the getEnv() static method of the System class in Java to fetch the value of the specified environment variable.
Syntax
public static String getenv(String name)
Parameters
String name: environment variable name.
Return value
The method returns the value for the given name. Otherwise, it returns null.
Code
In the code below, we fetch the values for two environment variables, PATH and JAVA_HOME.
public class Main {public static void main(String[] args) {System.out.println("PATH for Java: " + System.getenv("PATH"));System.out.println("Java Home: " + System.getenv("JAVA_HOME"));}}