Reader dustJsHelperReader = new InputStreamReader(dustHelperJsStream, encoding);
Context context = Context.enter();
context.setOptimizationLevel(9);
globalScope = context.initStandardObjects();
context.evaluateReader(globalScope, dustJsReader, dustJsFilePath, dustJsStream.available(), null);
context.evaluateReader(globalScope, dustJsHelperReader, dustJsHelperFilePath,
dustHelperJsStream.available(), null);
} catch (Exception e) {
logger.error("thrown exception when initialize step!", e);