Uses of JobExecutionDecider in Spring Batch split flow using SimpleAsyncTaskExecutor

Question

I want to configure a Spring Batch job with 4 steps. Step-2 and Step-3 are independent to each other. So I want to execute then in parallel. Any of these 2 steps or both can be skipped depending on Execution Parameter. Check the flow as mentioned below : Batch flow details

Java Configuration as mentioned below:

@Bean
public Job sampleBatchJob()
    throws Exception {

final Flow step1Flow = new FlowBuilder<SimpleFlow>("step1Flow")
        .from(step1Tasklet()).end();

final Flow step2Flow = new FlowBuilder<SimpleFlow>("step2Flow")
        .from(new step2FlowDecider()).on("EXECUTE").to(step2MasterStep())
        .from(new step2FlowDecider()).on("SKIP").end(ExitStatus.COMPLETED.getExitCode())
        .build();
final Flow step3Flow = new FlowBuilder<SimpleFlow>("step3Flow")
        .from(new step3FlowDecider()).on("EXECUTE").to(step3MasterStep())
        .from(new step3FlowDecider()).on("SKIP").end(ExitStatus.COMPLETED.getExitCode())
        .build();

final Flow splitFlow = new FlowBuilder<Flow>("splitFlow")
        .split(new SimpleAsyncTaskExecutor())
        .add(step2Flow, step3Flow)
        .build();

return jobBuilderFactory().get("sampleBatchJob")
        .start(step1Flow)
        .next(splitFlow)
        .next(step4MasterStep())
        .end()
        .build();
}

Sample code for Step2FlowDecider:

public class Step2FlowDecider
    implements JobExecutionDecider {
@Override
public FlowExecutionStatus decide(JobExecution jobExecution, StepExecution stepExecution) {

    if (StringUtils.equals("Y", batchParameter.executeStep2())) {
        return new FlowExecutionStatus("EXECUTE");
    }
    return new FlowExecutionStatus("SKIP");
}

}

With this configuration, when I try to execute the batch, it is getting failed, without any details error log.