code: public static <T> T executeIn(ClassLoader loader, Callable<T> task) throws Exception
     {
        if (task == null)
           return null;
  
        if (log.isLoggable(Level.FINE))
        {
           log.fine("ClassLoader [" + loader + "] task began.");
        }
        ClassLoader original = SecurityActions.getContextClassLoader();
        try
        {
           SecurityActions.setContextClassLoader(loader);
           return task.call();
        }
        finally
        {
           SecurityActions.setContextClassLoader(original);
           if (log.isLoggable(Level.FINE))
           {
              log.fine("ClassLoader [" + loader + "] task ended.");
           }
        }
     }
docs: Execute the given {@link Callable} in the {@link ClassLoader} provided. Return the result, if any.