code: public BatchFraction defaultThreadPool(final String name, final int maxThreads, final int keepAliveTime, final TimeUnit keepAliveUnits) {
          threadPool(name, maxThreads, keepAliveTime, keepAliveUnits);
          return defaultThreadPool(name);
      }
docs: Creates a new thread-pool and sets the created thread-pool as the default thread-pool for batch jobs.
  
  @param name           the maximum number of threads to set the pool to
  @param keepAliveTime  the time to keep threads alive
  @param keepAliveUnits the time unit for the keep alive time
  @return this fraction