public void testRestrict() throws Exception {
JexlContext context = new MapContext();
context.set("System", System.class);
Sandbox sandbox = new Sandbox();
// only allow call to currentTimeMillis (avoid exit, gc, loadLibrary, etc)
sandbox.white(System.class.getName()).execute("currentTimeMillis");
// can not create a new file
sandbox.black(java.io.File.class.getName()).execute("");
Uberspect uber = new SandboxUberspectImpl(null, sandbox);
JexlEngine sjexl = new JexlEngine(uber, null, null, null);