How define a spring batch chunk in the tasklet with code

Question

I have a spring-batch xml-based configuration that should be migrated to annotation-based configuration.

but I can't find any solution to define a chunk into the tasklet definition.

There are my xml and code base decleration:

 <step id="files2Memory">
        <tasklet>
            <chunk reader="pointFileReader" processor="pointFileProcessor"
                   writer="pointFileWriter" commit-interval="50000"/>
        </tasklet>
</step>

public Step files2Memory() {
    return stepBuilders.get("files2Memory")
            .tasklet(new Tasklet() {
                @Override
                public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext) throws Exception {
                    return null;
                }
            })
            .chunk(50000)
            .reader(new PointFileReader())
            .writer(new PointFileWriter())
            .processor(new PointFileProcessor())
            .build();
}

Best Regards

Answer 1

Mark PointFileReader and PointFileWriter PointFileProcessor with @Component, use @Scope("step") if required. Make Sure component scan cover them.

In you batch config file autowried the above.

@Autowired
private PointFileWriter pointFileWriter ;
@Autowired
private PointFileReader  pointFileReader ;
@Autowired
private ItemProcessor<TypeFromReader, TypeForWriter> pointFileProcessor ;

@Autowired
private PlatformTransactionManager transactionManager;
...
@Bean
protected Step files2Memory(){
        return steps
        .get("files2Memory")
        .transactionManager(transactionManager)
        .<TypeFromReader, TypeForWriter> chunk(5000)
        .reader(pointFileReader )
        .processor(pointFileProcessor)
        .writer(pointFileWriter).build();
    }

If one of the PointFileReader and PointFileWriter PointFileProcessor can not be specif as PointFileReader and PointFileWriter PointFileProcessorPointFileReader and PointFileWriter @Component you can defined them as @Beans and replace fields with method call

e.g.

@Bean
protected ItemReader<TypeFromReader> pointFileReader()  {
        PointFileReader <TypeFromReader> reader = new PointFileReader <TypeFromReader>();
        reader.set(...)
        return reader;
}

Answer 2

just remove the .tasklet part and if you want to be typesafe, use .<TypeFromReader, TypeForWriter>chunk

.tasklet is for custom Tasklets, .chunk already provides you the (hidden) chunkbased implementation