code: public int stop(String home)
     {
        Process p = instances.get(home);
        if (p != null)
        {
           try
           {
              p.destroy();
              return p.exitValue();
  
           }
           catch (Throwable t)
           {
              return -1;
           }
           finally
           {
              instances.remove(home);
           }
        }
  
        return 0;
     }
docs: Stop an instance
  @param home The home directory
  @return The exit code