code: @Override
  	public void setPrefix(final String prefixString) {
  		lock.writeLock().lock();
  		try {
  			if (prefixString == null || StringUtils.isBlank(prefixString)) {
  				localPrefix.remove();
  			} else {
  				if (prefixes != null) {
  					if (!prefixes.contains(prefixString)) {
  						throw new IllegalArgumentException("The given prefix is not part of the prefixes.");
  					}
  				}
  				localPrefix.set(prefixString);
  			}
  		} finally {
  			lock.writeLock().unlock();
  		}
  	}
docs: Sets the prefix for the current thread.
  
  @param prefixString
  the new prefix