@Override
public List<ExternalIoStage> emitPrologue(IoContext context) throws IOException {
List<CopyDescription> targets = Lists.create();
for (Input input : context.getInputs()) {
InputDescription description = input.getDescription();
FileImporterDescription desc = extract(description);
if (isCacheTarget(desc)) {
targets.add(new CopyDescription(
getProcessedInputName(description),
getEnvironment().getDataClasses().load(description.getDataType()),
getOrifinalInputInfo(desc),