Convert Message to Job to make it Spring Integrati

Question

I am trying to process a series of files using Spring Integration in a batch fashion. I have this very old xml which tries to convert the messages into jobs

    <int:transformer ref="messageToJobTransformer"/>
    <batch-int:job-launching-gateway job-launcher="jobLauncher"/>

The messageToJobTransformer is a class which can convert a Message into a Job. The problem is I don't know where this file is now neither I want a xml config. I want it to be pure Java DSL. Here is my simple config.

return IntegrationFlows.from(Files.inboundAdapter(directory)
                    .preventDuplicates()
                    .patternFilter("*.txt")))
                    .handle(jobLaunchingGw())                       
                    .get();

And here is my bean for the gateway.

@Autowired
private JobLauncher jobLauncher;

@Bean
public MessageHandler jobLaunchingGw() {
    return new JobLaunchingGateway(jobLauncher);   
}

EDIT:Updating the Batch Config class.

@Configuration
    @EnableBatchProcessing
public class BatchConfig

{

@Autowired
private JobBuilderFactory jobs;

@Autowired
private StepBuilderFactory steps;




@Bean
        public ItemReader<String> reader(@Value({jobParameters['input.file.name']}") String filename) throws MalformedURLException
    {
        FlatFileItemReader<String> reader = new FlatFileItemReader<String>();       
        return reader;
    }
@Bean
public Job job() throws MalformedURLException
{
    return jobs.get("job").start(step()).build();
}

@Bean
public Step step() throws MalformedURLException
{
    return steps.get("step").<String, String> chunk(5).reader(reader())
    .writer(writer()).build();
}

@Bean
public ItemWriter<String> writer(@Value("#{jobParameters['input.file.name']}")
{
    FlatFileItemWriter writer = new FlatFileItemWriter();
    return writer;
}



}

Answer 1

Your question isn't clear. The JobLaunchingGateway expects JobLaunchRequest as a payload.

Since your Integration Flow begins from the Files.inboundAdapter(directory), I can assume that you that you have there some Job definitions. So, what you need here is some class which can parse the file and return JobLaunchRequest.

Something like this from the Spring Batch Reference Manual:

public class FileMessageToJobRequest {
    private Job job;
    private String fileParameterName;

    public void setFileParameterName(String fileParameterName) {
        this.fileParameterName = fileParameterName;
    }

    public void setJob(Job job) {
        this.job = job;
    }

    @Transformer
    public JobLaunchRequest toRequest(Message<File> message) {
        JobParametersBuilder jobParametersBuilder =
            new JobParametersBuilder();

        jobParametersBuilder.addString(fileParameterName,
            message.getPayload().getAbsolutePath());

        return new JobLaunchRequest(job, jobParametersBuilder.toJobParameters());
    }
}

After the definition that class as a @Bean you can use it from the .transform() EIP-method just before your .handle(jobLaunchingGw()).

UPDATE

@Bean
public FileMessageToJobRequest fileMessageToJobRequest(Job job) {
     FileMessageToJobRequest fileMessageToJobRequest = new FileMessageToJobRequest();
     fileMessageToJobRequest.setJob(job);
     fileMessageToJobRequest.setfileParameterName("file");
     return fileMessageToJobRequest;
}
...

@Bean
public IntegrationFlow flowToBatch(FileMessageToJobRequest fileMessageToJobRequest) {

      return IntegrationFlows
            .from(Files.inboundAdapter(directory)
                    .preventDuplicates()
                    .patternFilter("*.txt")))
            .transform(fileMessageToJobRequest)
            .handle(jobLaunchingGw())                       
                    .get();

}