code: @Nonnull
  	public static CachingXmlDataStore createCachingXmlDataStore(@Nonnull final URL dataUrl, @Nonnull final URL versionUrl,
  			@Nonnull final Charset charset, @Nonnull final DataStore fallback) {
  		return createCachingXmlDataStore(findOrCreateCacheFile(), dataUrl, versionUrl, charset, fallback);
  	}
docs: Constructs a new instance of {@code CachingXmlDataStore} with the given arguments. The file used to cache the
  read in <em>UAS data</em> will be called from {@link CachingXmlDataStore#findOrCreateCacheFile()}. This file may
  be empty or filled with previously cached data in XML format. The file must be writable otherwise an exception
  will be thrown.
  
  @param dataUrl
  URL to <em>UAS data</em>
  @param versionUrl
  URL to version information about the given <em>UAS data</em>
  @param charset
  the character set in which the data should be read
  @param fallback
  <em>UAS data</em> as fallback in case the data on the specified resource can not be read correctly
  @return new instance of {@link CachingXmlDataStore}
  @throws net.sf.qualitycheck.exception.IllegalNullArgumentException
  if one of the given arguments is {@code null}
  @throws net.sf.qualitycheck.exception.IllegalStateOfArgumentException
  if the given cache file can not be read