how to execute single jar code example

Example 1: java execute jar from main

java -cp MyJar.jar com.packagename.MainClass [somearg1] [somearg2] [etc]

Example 2: run jar file with different jre

First, go to the location of the java installation file. By default, this is:
C:\Program Files\Java\...
Open the folder of the java version you want and go to the bin folder.
Copy the directory your at then go to your command line. 
Syntax: (%PATH% is path you copied):
"%PATH%/java.exe" [javaArgs] [filePath] [yourCodeArgs]