code: protected void initForEachRun() throws EXIException, IOException {
  
  		// clear runtime data
  		this.runtimeGlobalElements.clear();
  		for (int i = 0; i < nextUriID; i++) {
  			this.runtimeUris.get(i).clear();
  		}
  
  		// re-set schema-informed grammar IDs
  		nextUriID = this.gUris;
  
  		// possible document/fragment grammar
  		Grammar startRule = exiFactory.isFragment() ? grammar
  				.getFragmentGrammar() : grammar.getDocumentGrammar();
  
  		// (core) context
  		elementContextStackIndex = 0;
  		elementContextStack[elementContextStackIndex] = elementContext = new ElementContext(
  				null, startRule);
  	}
docs: re-init (rule stack etc)