Spring Batch - Validate Header Lines in input csv file and skip the file if it invalidates

Question

I have a simple job as below:

Answer 1

Looking code of FlatFileItemReader file stop condition is managed;

1. with private field boolean noInput
2. with private function readLine() used in protected doRead()

IMHO the best solution is to throw a runtime exception from your skippedLineCallback and manage error as reader exhaustion condition.

Foe example writing your delegate in this way

class SkippableItemReader implements ItemStreamReader {
  private ItemStreamReader flatFileItemReader;
  private boolean headerError = false;

  void open(ExecutionContext executionContext) throws ItemStreamException {
    try {
      flatFileItemReader.open(executionContext);
    } catch(MyCustomExceptionHeaderErrorException e) {
      headerError = true;
    }
  }

  public T read() {
    if(headerError)
      return null;
    return flatFileItemReader.read();
  }

  // Other functions delegation
}

(you have to register delegate as stream manually,of course)
or extending FlatFileItemReader as

class SkippableItemReader extends FlatFileItemReader {
  private boolean headerError = false;

  protected void doOpen() throws Exception {
    try {
      super.doOpen();
    } catch(MyCustomExceptionHeaderErrorException e) {
      headerError = true;
    }
  }

  protected T doRead() throws Exception {
    if(headerError)
      return null;
    return super.doRead();
  }    
}

The code has been written directly without test so there can be errors, but I hope you can understand my point.
Hope can solve your problem