@Override
    public void finishCacheXml(String name) {
      try {
        File file = temporaryFolder.newFile(name + "-cache.xml");
        PrintWriter printWriter = new PrintWriter(new FileWriter(file), true);
        CacheXmlGenerator.generate(getCache(), printWriter);
        printWriter.close();
        close();
        GemFireCacheImpl.testCacheXml = file;
        createCache.run();
      } catch (Exception ex) {
        throw new RuntimeException(ex);
      } finally {
        GemFireCacheImpl.testCacheXml = null;
      }
    }
Finish what {@code beginCacheXml} started. It does this be generating a cache.xml file and
then creating a real cache using that cache.xml.
geode-dunit/src/main/java/org/apache/geode/test/dunit/rules/CacheXmlRule.java