Windows 10 and Windows 8
In Search, search for and then select: System (Control Panel)
Click the Advanced system settings link.
Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New.
In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.
Reopen Command prompt window, and run your java code.
Mac OS X
To run a different version of Java, either specify the full path or use the java_home tool:
% /usr/libexec/java_home -v 1.8.0_73 –exec javac -version
Solaris and Linux
To find out if the path is properly set:
In a terminal windows, enter:
% java -version
This will print the version of the java tool, if it can find it. If the version is old or you get the error java: Command not found, then the path is not properly set.
Determine which java executable is the first one found in your PATH
In a terminal window, enter:
% which java
