code: @Override
  	public boolean startsWithCurrentPrefix(final String key) {
  		lock.readLock().lock();
  		try {
  			if (getPrefix() != null && key != null) {
  				return key.startsWith(getPrefix() + getPrefixDelimiter());
  			}
  		} finally {
  			lock.readLock().unlock();
  		}
  		return false;
  	}
docs: /*
  (non-Javadoc)
  
  @see
  net.sf.prefixedproperties.config.PrefixConfig#startsWithCurrentPrefix(
  java.lang.String)