code: public ConcurrentMap<String, L> getLoggersInContext(final LoggerContext context) {
          ConcurrentMap<String, L> loggers;
          lock.readLock ().lock ();
          try {
              loggers = registry.get (context);
          } finally {
              lock.readLock ().unlock ();
          }
  
          if (loggers != null) {
              return loggers;
          } else {
              lock.writeLock ().lock ();
              try {
                  loggers = registry.get (context);
                  if (loggers == null) {
                      loggers = new ConcurrentHashMap<> ();
                      registry.put (context, loggers);
                  }
                  return loggers;
              } finally {
                  lock.writeLock ().unlock ();
              }
          }
      }
docs: Gets or creates the ConcurrentMap of named loggers for a given LoggerContext.
  
  @param context the LoggerContext to get loggers for
  @return the map of loggers for the given LoggerContext