Dynamic file name for FileItemRead

[xnaud]

I am looking for a way to kick off a batch which has a filename as an input parameter.
the filename would be used by the FileItemReader to open the file and process it.

I have not found any good (for me) explanations about how to do it. I know that I should set the resource parameter of my file reader as follows:

<property name="resource"value="/data/input/${file.name}" />

but I still don't get how that works. Do I need to create a variable file.name in my parameter list?

Thanks

Xav

[lucasward]

It's covered in Chapter 3 of the reference documentation:

http://static.springframework.org/sp...e.html#d0e1694

Please let me know if after reading the docs you are still having issues. We're always trying to improve them.

[xnaud]

Thanks.

I see the doc has improved a lot recently.

Xav

[Raphael_Lemaire]

Hello.

The link is broken, and I couldn't find an explanation of how to use a batch parameter as a resource path (I end up using a custom laucher registering the
parameter as a System property, combined with a PropertyPlaceholderConfigurer).

[DHGarrette]

You'll want to use late-binding:
http://static.springframework.org/sp...l#late-binding

[Raphael_Lemaire]

Thank you.

I already try that syntax :

<property name="resource" value="#{jobParameters[input.file.name]}" />

But I must be missing something, the el expression is not interpreted and I end up with something like :

at org.springframework.batch.core.launch.support.CommandLineJobRunner.start(CommandLineJobRunner.java:207)
	at org.springframework.batch.core.launch.support.CommandLineJobRunner.main(CommandLineJobRunner.java:254)
Caused by: java.lang.IllegalStateException: Input resource must exist (reader is in 'strict' mode): class path resource [#{jobParameters[input.file.name]}]
	at org.springframework.batch.item.file.FlatFileItemReader.doOpen(FlatFileItemReader.java:245)
	at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.open(AbstractItemCountingItemStreamItemReader.java:108)
	... 18 more

Maybe there's an additional configuration required to use this feature ?

[DHGarrette]

Make sure that your <bean/> has scope="step"

[Raphael_Lemaire]

It's working now, thank you very much !

Here's the final config :

<bean id="theReader" class="org.springframework.batch.item.file.FlatFileItemReader">
        <property name="lineMapper">
            ...
        </property>        
        <property name="resource">
            <bean class="org.springframework.core.io.FileSystemResource" scope="step">
                <constructor-arg value="#{jobParameters[inputfilename]}" />
            </bean>
        </property>
    </bean>

[Raphael_Lemaire]

It might be useful to add this tip in the reference documentation.

Is there a process to submit a documentation update ?

[DHGarrette]

The subsequent section in the document is about StepScope, but I agree it might be nice to put a note so that readers are aware that the next section applies to them.

All issues (including Documentation issues) should be logged in JIRA: http://jira.springframework.org/browse/BATCH