public static boolean isPropertyRef( final PsiLiteralExpression expression, final String key, final String resourceBundleName) { if (resourceBundleName == null) { return !PropertiesImplUtil.findPropertiesByKey(expression.getProject(), key).isEmpty(); } else { final List<PropertiesFile> propertiesFiles = propertiesFilesByBundleName(resourceBundleName, expression); boolean containedInPropertiesFile = false; for (PropertiesFile propertiesFile : propertiesFiles) { containedInPropertiesFile |= propertiesFile.findPropertyByKey(key) != null; } return containedInPropertiesFile; } }