code: public WsByteBufferPoolManager getBufferManager() {
          ByteBufferConfiguration bbMgr = this.wsbbmgr;
  
          // Get the byte buffer manager-- bbMgr could return null
          WsByteBufferPoolManager result = (bbMgr == null) ? null : bbMgr.getBufferManager();
  
          // Fall back to a default if bbMgr was null or null was returned
          return result != null ? result : ChannelFrameworkFactory.getBufferManager();
      }
docs: Access the reference to the bytebuffer pool manager created by this
  bundle, or the default/fallback pool.
  
  This method should never return null
  
  @return WsByteBufferPoolManager