How to disable all network connections in Java

Question

Is there a way to run Java VM (java.exe) on Windows Server 2008 and disable all network connections using a command line argument or a system variable?

Answer 1

I had the same task to test offline installer for our product. All said above is almost right, but creating .policy file is not easy for the first time. Here is what I did:

1. Crated generic policy file that has no permission to resolve host names (see code snippet below);

2. Added -Djava.security.manager -Djava.security.policy=pathto/policy.file in jvm parameters;

generic .policy file content:

grant {
    permission java.io.FilePermission "<>", "read,write,execute,delete";
    permission java.util.PropertyPermission "*", "read,write";
    permission java.lang.RuntimePermission "*";
    permission java.net.NetPermission "*";
    permission java.lang.reflect.ReflectPermission "*";
};

If something tries to get content outside during the test, it fails with security exception.