code: public String getEffectivePrefix() {
  		lock.readLock().lock();
  		try {
  			final boolean useLocalPrefixes = !mixDefaultAndLocalPrefixes && hasLocalPrefixConfigurations();
  			return getPrefix(new StringBuilder(), useLocalPrefixes).toString();
  		} finally {
  			lock.readLock().unlock();
  		}
  	}
docs: Gets the effective prefix.
  
  @return the prefix