}
try {
final SourceValidity sourceValidity = this.startDocument.getSourceValidity();
final SourceValidity templateValidity = (SourceValidity) validityExpr.getValue(this.expressionContext);
if (sourceValidity != null && templateValidity != null) {
return new JXSourceValidity(sourceValidity, templateValidity);
}
} catch (Exception e) {
getLogger().error("error evaluating cache validity", e);
}
return null;