How to resolve the issue of environment variable changes not taking effect in Java?

If you have made changes to environment variables in Java but they are not taking effect, there are several potential solutions:

1. Make sure you have restarted any applications that rely on environment variables. After modifying the environment variables, you need to restart the applications for the changes to take effect.
2. Check if you have correctly modified the environment variables. On a Windows system, you can use the command “echo %variable name%” in the command prompt to check if the value of the environment variable has been modified. On Linux or Mac systems, you can use the command “echo $variable name” to check the value of the environment variable.
3. Ensure that you are modifying the correct environment variable. Sometimes, you may mistakenly modify a variable that is unrelated to the one you intended to change. Please carefully review your modifications.
4. Ensure that you have sufficient permissions to modify the environment variables. In some cases, you may need to run the application or command prompt as an administrator in order to modify the environment variables.
5. If you have made changes to the environment variables in your Java code but they are not taking effect, make sure you have recompiled and rerun the code.

If the above methods do not solve the problem, it may be due to other reasons causing the environmental variable changes to not take effect. In this case, you can try using alternative methods to set or modify the environmental variables, such as using the interface provided by the operating system or editing configuration files.