How can you run Javascript using Rhino for Java in a sandbox?

To guard against infinite loops, you can observe the instruction count as the script runs (this works only with interpreted scripts, not with compiled ones).

There is this example in the Rhino JavaDocs to prevent a script from running for more than ten seconds:

 protected void observeInstructionCount(Context cx, int instructionCount)
 {
     MyContext mcx = (MyContext)cx;
     long currentTime = System.currentTimeMillis();
     if (currentTime - mcx.startTime > 10*1000) {
         // More then 10 seconds from Context creation time:
         // it is time to stop the script.
         // Throw Error instance to ensure that script will never
         // get control back through catch or finally.
         throw new Error();
     }
 }