Question

如何为每次运行的作业初始化MultiResourceItemReader。当前使用此设置，其每次运行作业仍使用相同的实例

我将@StepScope仍旧使用已处理过的文件的旧列表。我不确定在此代码中还需要添加什么

我还尝试了@JobScope，但也没有成功。我缺少一些基本的东西

@Configuration
@EnableBatchProcessing
public class BatchConfiguration {

    @Autowired
    public JobBuilderFactory jobBuilderFactory;
    @Autowired
    public StepBuilderFactory stepBuilderFactory;


    @Value("file:ftp-inbound/*.csv")
    @Autowired
    private Resource[] inputResources;

    @Autowired
    private StepBuilderFactory steps;
    @Autowired
    private JobBuilderFactory jobs;
    @Autowired
    private ResourceLoader resourceLoader;


    @Bean
    public FlatFileItemReader<AccommodationRoomAvailability> itemReader() throws UnexpectedInputException, ParseException, IOException {
        FlatFileItemReader<AccommodationRoomAvailability> reader = new FlatFileItemReader<AccommodationRoomAvailability>();
        DelimitedLineTokenizer tokenizer = new DelimitedLineTokenizer();
        String[] tokens = {"Product ID", "Allotment", "Kamertype", "Zoeknaam", "Hotel", "Datum", "Beschikbaar", "Nachten"};
        tokenizer.setNames(tokens);
        tokenizer.setDelimiter(";");
        tokenizer.setStrict(true);
        reader.setLinesToSkip(1);
        DefaultLineMapper<AccommodationRoomAvailability> lineMapper = new DefaultLineMapper<AccommodationRoomAvailability>();
        lineMapper.setLineTokenizer(tokenizer);
        lineMapper.setFieldSetMapper(new RecordFieldSetMapper());
        reader.setLineMapper(lineMapper);

        return reader;
    }

    @Bean
    @Qualifier("multiResourceReader")
    @StepScope
    public MultiResourceItemReader<AccommodationRoomAvailability> multiResourceItemReader() throws Exception {
        MultiResourceItemReader<AccommodationRoomAvailability> resourceItemReader = new MultiResourceItemReader<AccommodationRoomAvailability>();
        resourceItemReader.setResources(inputResources);
        resourceItemReader.setDelegate(itemReader());
        resourceItemReader.setStrict(false);
        resourceItemReader.setSaveState(false);

        // resourceItemReader.read();
        return resourceItemReader;
    }

    @Bean
    public ItemProcessor<AccommodationRoomAvailability, String> itemProcessor() {
        return new AvailabilityProcessor();
    }

    @Bean
    public ItemWriter itemWriter() {
        return new ItemWriter() {
            @Override
            public void write(List list) throws Exception {


            }
        };
    }

    @Bean
    protected Step step1(@Qualifier("multiResourceReader") MultiResourceItemReader<AccommodationRoomAvailability> reader, ItemProcessor<AccommodationRoomAvailability, String> processor,
                         ItemWriter writer) {
        return steps.get("step1")/*.listener(new StepListener())*/.<AccommodationRoomAvailability, String>chunk(30000).reader(reader)
                .processor(processor)
                .writer(writer)
                .build();
    }

    @Bean
    public Step step2() throws IOException {

        FileDeletingTasklet task = new FileDeletingTasklet();
        task.setResources(inputResources);
        return stepBuilderFactory.get("step2")
                .tasklet(task)
                .build();
    }

    @Bean(name = "job")
    public Job job(@Qualifier("step1") Step step1, Step step2) throws IOException {
        return jobs.get("job")
                .start(step1).on("*").to(step2).end()
                // .flow(step1).on("").to(step2()).end()
                .build();
    }

}

Answer 1

一旦创建了应用程序上下文，注入的资源@Value("file:ftp-inbound/*.csv")在应用程序的整个生命周期中都是相同的。这就是为什么读者将始终读取相同的值的原因。

您需要将这些资源作为参数传递给您的工作，并将它们后期绑定到您的阅读器中，并具有Step范围。在您的示例中，它将类似于：

@Bean
@Qualifier("multiResourceReader")
@StepScope
public MultiResourceItemReader<AccommodationRoomAvailability> multiResourceItemReader(@Value("#{jobParameters['inputResources']}") Resource[] inputResources) throws Exception {
    MultiResourceItemReader<AccommodationRoomAvailability> resourceItemReader = new MultiResourceItemReader<AccommodationRoomAvailability>();
    resourceItemReader.setResources(inputResources);
    resourceItemReader.setDelegate(itemReader());
    resourceItemReader.setStrict(false);
    resourceItemReader.setSaveState(false);

    return resourceItemReader;
}

然后将输入资源作为参数传递给您的工作：

JobParameters jobParameters = new JobParametersBuilder()
            .addString("inputResources", "file:ftp-inbound/*.csv")
            .toJobParameters();

当前使用此设置，它仍然为每个作业运行使用相同的实例

这是因为当您将资源注入配置类的字段中时，它们总是相同的。如果您使用我在上一个示例中提到的作业参数方法，那么使用不同的文件集运行作业将有不同的实例。

如何为每个作业运行重置MultiResourceItemReader。步骤范围不起作用

1 个答案: