Question

I have a spring-batch job that converts various bank statements into my app. There is a different reader for each bank statement type and only one writer for all of them. The job is very simple – read, process and write:

<batch:job id="importer" restartable="true">
    <batch:step id="import">
        <batch:tasklet>
            <batch:chunk reader="reader" writer="writer" processor="processor" commit-interval="10" />
        </batch:tasklet>
    </batch:step>
</batch:job>

Now, I would like the end user to provide a statement file as well as bank information and then choose a corresponding spring-batch reader at runtime for this job to run. Ideally it would be great if I could read-ahead in a first step and tried to “guess” the bank form statement format first. But I digress.

Is it possible to inject a reader into a job prior to running it? Or is there a better way to achieve my goal?

Answer 1

You can set the reader from an input parameter/or a propeties file:

<batch:chunk reader="#{jobParameters['reader.beanId']}" writer="writer" processor="processor" commit-interval="10" />

Also you could consider late binding of job and step attributes, here is the link from spring-batch step-scope